The Perfect Recovery Circuit!

So I have accepted the challenge/opportunity (depending on if you are into poison or medicine) to write in the fitness section of AZ Foothills Magazine each month. As you can see it's already the 2nd of July and my article is due the 5th (so I need to get to it!). As a post-rehab specialist I have learned over throughout the years the huge benefits you can get from doing the following healing modalities: cryotherapy, isokinetic resistance training, and infrared sauna. Each one of these therapies are extremely beneficial to the body, but I've discovered that by combining these 3 elements you get an awesome synergistic trifecta! The foundation for healing is anti-inflammation, thus doing things to your body (i.e. crazy cross-fit or acidic foods) to inflame it is not smart (muy malo). Life in general is pretty inflammatory, so if you find a program that helps "de-flame" the body you're on the right track. If you are interested in trying this circuit out contact me and I'll gladly take you through this "Recovery Circuit." Proof is in the pudding, if it is everything that I claim it to be than you have found your "Holy Grail" for recovery. Here's a brief break down of the benefits as you go through this amazing circuit:

Recovery Circuit Steps:

Step 1: Cryotherapy - Exposure to sub-zero temperature activates the central nervous system. The central nervous system (when activated) allows the release of beneficial hormones and enhances circulation. The hormones released produces a systemic response that provides pain relief, increased mobility, decreased inflammation, and mood elevation. 

Step 2: Recovery Warm-Up on the revolutionary CorePump® Machine - The CorePump® Machine provides isokinetic resistance, which is a safe, effective and efficient way to strengthen the entire body (without the inflammation typically associated with traditional exercise). You will also safely increase your flexibility as well as improve your cardiovascular/cardiopulmonary health.

Step 3: Infrared Sauna - The health benefits that you get from the infrared saunas are: Heart health and blood pressure, detoxification (eliminate toxic heavy metals), anti-aging, muscle growth, injury healing, weight loss, metabolic diseases, mood, mental health, cognitive function, inflammation, autoimmunity, and skin health. 

I could write a book on the benefits of these modalities because they are so numerous.

If you are interested in learning more about these benefits email me and I'll send you more information. 

 

What Is Involved In The First Hour?

Younger Tomorrow: The First Hour involves the following elements: cryotherapy, isokinetic training, infrared sauna, meditation and nutrients that help make the body alkaline. 

Here is a high level list of some of the basic benefits from each (we'll dive deeper into each topic in later blogs). 

Cryotherapy: 

  • Pain relief and muscle healing. ...
  • Weight Loss. ...
  • Reduced inflammation. ...
  • Preventing dementia. ...
  • Preventing and treating cancer. ...
  • Reducing anxiety and depression. ...
  • Improving symptoms of eczema. ...
  • Treating Migraine Headaches.

Isokinetic Resistance Training:

Isokinetic exercise is a type of strength training. It uses specialized exercise machines that produce a constant speed no matter how much effort you expend. These machines control the pace of an exercise by fluctuating resistance throughout your range of motion. Your speed remains consistent despite how much force you exert.

You can adjust the target exercise speed and range of motion to suit your needs. Different attachments on the machines can isolate and target specific muscle groups. You can use Isokinetic exercise to test and improve your muscular strength and endurance.

Infrared Sauna:

  • Detoxification. Sweating is one of the body's most natural ways to eliminate toxins, making it a crucial part of detoxification. ...
  • Relaxation. ...
  • Pain Relief. ...
  • Weight Loss. ...
  • Improved Circulation. ...
  • Skin Purification.

Meditation:

  • Meditation reduces stress.
  • It improves concentration. “I'm more centered and focused in everything I do. ...
  • It encourages a healthy lifestyle.
  • The practice increases self-awareness. ...
  • It increases happiness.
  • Meditation increases acceptance. ...
  • It slows aging.
  • The practice benefits cardiovascular and immune health.

Alkaline Diet:

Disease thrives in an acidic environment and dies in an alkaline diet. I like to keep things super simple. If a food class (ie animal products) produces acid, then it will cause inflammation in the body which is the distress call by the body that there is dis-ease occurring. For the most part I like to keep my diet strictly plant based, staying far away from animal products high in acidity (ie pork, red meat, fowl, dairy, etc...). Trust me there are so many foods out there that are quite delicious that grew from the ground (didn't have a mamma). 

I hope this high level view on my approach to the basics of The First Hour has been helpful and eye opening for you. 

Peace and Love

The 1st Hour. Purpose

My purpose for writing The 1st Hour came to me this morning while I woke up without my alarm (my phone died and I didn't want to go out to my car to get the charger) at 4am. I felt like I could have went back to bed, but I wanted to get to work on a ClickFunnels campaign that I am starting to build. As I laid in bed I realized that all of the "Greats" or "Success Stories" all seemed to have had the same habit first thing upon rising. Some go crazy like "making your bed" or "meditate" for an insane amount of time. I'm on the same page as Tim Ferriss regarding making the most out of each second of each day. I don't like to divide my days into seconds, minutes, or hours anymore. When I do I seem to watch my days fly into weeks, months, years and then holy shit, decades! No I've decided upon rising this morning to divide my time into moments. If I could recreate the calendar it would be a calendar of moments. That way life isn't about the number of days you survived on this rock, but the number of moments you've experienced. Makes sense right? Who cares if you're 199 years old with only 29 moments, I'd rather be 29 years old with 199 moments. 

Anyways back to the "purpose" at hand, The 1st Hour. 

BENEFITS OF HYDRAULIC RESISTANCE EXERCISE

BENEFITS OF HYDRAULIC RESISTANCE EXERCISE

Backed by 20 years of research and development, Hydra-Fitness Industries offers the safest and most effective exercise/rehabilitation equipment on the market today.

These unique machines, with their patented hydraulic system, work on many different levels to meet widely varying needs such as strength, power, endurance, cardiovascular conditioning, aerobic and anaerobic training, rehabilitation and cardiopulmonary activity.

Muscle contractions

In order to appreciate the nature of hydraulic resistance exercise with Hydra Fitness equipment, a brief discussion of the various types or classifications of muscle contraction is in order.

An isometric contraction occurs when the muscle develops tension but does

not change length. No movement occurs because the resistance is greater than the force potential of the muscle. A sub-maximal isometric contraction is termed a "static" contraction.

An isotonic contraction occurs when the resistance or load remains the same

and there is movement involved. That is, the force developed by the muscle overcomes the inertia of the resistance. In an isotonic contraction the velocity of the movement is not necessarily controlled, but rather the main classification characteristic is the constant load.

An isokinetic contraction is defined as occurring at a fixed velocity. In

practice this refers to a constant velocity of movement in a body part or segment rather than a fixed speed of shortening within the muscle.

Functional isokinetics provides all the accommodations or variable resistance of isokinetic training, but with variable speed and maximum overload at every joint angle throughout any range ofmotion.

Most isokinetic devices provide variable or accommodating resistance, which implies that the resistance is maximized according to the ability of the muscle to generate tension. The ability to generate tension is affected by the mechanical properties inherent in the lever system comprised of muscle and bone. In other words, there are "strong" and "weak" points in the normal range of motion which are usually referenced to the angle between the body segment(s) and the involvedjoint(s).

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In an isotonic contraction, the greatest weight that can be moved through a normal range of motion is limited by what can be moved at the weakest joint angle. Therefore, the muscle is provided with maximal overload at that point only. There are usually ranges of strong and weak joint angles, but the degree of overload at the strongest joint angle is dramatically restricted if the movement is performed through the full range of movement. An alternative is to work with heavier resistance through a restricted range of stronger joint angles, which is effective, but time-consuming.

The major advantage of a system which provides accommodating resistance is that the muscle is able to generate more external force and the system provides more resistance. Many scientists and fitness professionals feel that such loading systems are superior to traditional isotonic or constant-load systems. Hydra-Fitness uses "functional isokinetics." This comprises all theadvantages of "isokinetics," but with "variable speeds" instead of non-functional fixed speeds.

Strength, power and velocity
Strength is often defined as the maximal tension genera ted by a muscle. Functionally, a

maximal isometric con traction at the strongest joint angle results in the greatest force.

Power is often defined as work accomplished relative to the time required to perform it. Since work is the product of force times distance, and work divided by time is power, the speed of movement can dramatically influence the power output of muscle. If a muscle can be trained for both force and speed, performance can be maximized. 'Performing at both high resistance and high speed is critical for peak performance of some athletes. Since high-velocity training with conventional weight-based systems is neither practical nor safe, hydraulic resistance systems have a great advantage due to their ability to accommodate both resistance and velocity safely.

The "specificity of training" principle

Specificity is one of the most important underlying principles governing the success of

While exercise scientists do not yet fully appreciate the nature of this

training.
principle, it appears that maximal benefits occur when training is specific to the performance. Very simply, strength training tends to enhance strength, and aerobic training enhances endurance. But the issue becomes very complicated when athletes are preparing for competition. Sport specific training is not always possible (e.g. rowing in the winter) or desirable (constant training in one mode may cause boredom or · decrease motivation); therefore, alternatives are very important. However, in order to "transfer" as much of the training effect as possible to the actualperformance, the specificity principle must be adhered to.

Training with hydraulic resistance allows movement patterns and movement velocities nearer

to the actual performance. thereby enhancing the specificity effect.

Cardiorespiratory fitness

Circuit training with variable resistance hydraulic equipment is becoming increasingly popular. It involves a cardiovascular response that results in improved aerobic fitness. By using a variety of work-to-rest ratios in a circuit mode, both anaerobic and aerobic energy systems can be stressed. Circuit training with the variable resistance Hydra-Fitness systems at a high cardiorespiratory involvement can induce positive aerobic power training effects. When conducted at relatively high velocities with a work-to-rest ratio, the cardiovascular system will be stressed. This effect on the cardiovascular system has not been observed with circuit training on other strength -training equipment.

Traditionally, strength training exercises have not been utilized for cardiac rehabilitation because they were believed to represent increased risk for the patient. However, more recent studies have demonstrated the relative safetyof weight-carrying and circuit weight training exercises among cardiac patients who were only three months post-clinical. The addition of Hydra Fitness circuit training to medically supervised cardiac exercise programs mayenhance the patients' ability to meet many of the physical demands associated with their daily activities.

In summary, Hydra-Fitness resistance training systems uniquely provide the opportunity to exercise with accommodating resistance over a wide range of movement velocities. Most Hydra-Fitness systems offer alternating resistance and the choice of unilateral or bilateral movements. The equipment is well suited to circuit training and appears to provide excellent strength training gains from short-term programs.

Clearly, any training program is dictated by the need and the initial fitness level of the individual. The Hydra-Fitness line of resistance exercise systems can be adapted safely and effectively, regardless of the training objectives.

Fitness among the aging population

An often observed and reported trend among the elderly is loss of muscle, gain in fat and decline in overall body composition -- a condition that is not necessarily normal, but rather may be a result of lack of the proper type of exercise. Any exercise can significantly increase muscle mass and decrease

body fat content; however, conventional exercise equipment is not readily accepted by the aging. It is often viewed as intimidating and unsafe. Hydra Fitness equipment has been the single

alternative for fitness among the aging population due to its accommodating resistance, allowing

anyone at any age to begin exercising at their own level of fitness.

Evaluation of acute cardiorespiratory responses to hydraulic resistance exercise

ABSTRACT

F.I. KATCH, P.S. FREEDSON, and C.A. JONES. Evaluation of acute cardiorespiratory responses to hydraulic resistance exercise. Med. Sci. Sports Exerc., Vol. 17, No. 1, pp. 168-173, 1985. Accurate evaluation of the acute responses to resistance exercise training depends on the stability of the criterion measures. This is particularly true for maximal effort exercise where continuous "all-out" effort for each repetition is encouraged. The present study evaluated reliability of repetition number (repN), respiratory gas parameters (VO2, VCO2, VE), and heart rate (HR) for shoulder (SE), chest (CE), and leg (LE) exercise performed maximally on a single- unit, 3-station hydraulic resistance exercise machine (Hydra-Fitness, Belton, TX). On 2 separate days, 20 college men completed three 20-s bouts of SE, CE, and LE with a 20-s rest between bouts and 5 min between exercise modes. There were no significant differences between bouts or test days for repN, gas measures, or HR. Subjects performed 17, 19, and 21 reps during SE, LE, and CE. VO2 was 1.7 1.min-1 (24.3 ml.kg-1.min-1) for SE, 1.87 min-1 (25.5 ml.kg-1 .min-1) for CE, and 2.1 1.min-1 (28.6 ml .kg-1 min-1) for LE. These values, averaged, represented 52.8% of the max Vol determined on a continuous cycle ergometer test. The corresponding HR's during hydraulic exercise averaged 84.6% of HR max. Test-retest reliability coefficients ranged from r= .67 to .87 for repN, r = .41 to .83 for gas measures, and r = .72

to .89 for HR. The MET level averaged 7.5 (heavy), and caloric expenditure per minute averaged 35% higher compared with literature values for free weights and 29.4 and 11.5% greater than circuit exercise on Nautilus or Universal Gym equipment, respectively. It is concluded that there are reliable individual differences in repN, respiratory gas parameters, and HR during maximal effort exercise of relatively short duration performed on a multiple- station hydraulic resistance exercise apparatus.

HYDRAULIC RESISTANCE EXERCISE, RESPIRATION, GAS EXCHANGE, HEART RATE, CARDIOVASCULAR RESPONSE, CALORIC EXPENDITURE, EXERCISE INTENSITY, RELIABILITY, OXYGEN CONSUMPTION

Circuit weight training improves muscular strength and cardiovascular fitness (4-7, 18). The duration of a single circuit usually varies between 7 and 12 min for a 10-station routine, depending on the rest interval between exercises (15-60 s) and the number of repetitions performed per exercise (6-15 reps). Research with circuit weight training includes conventional free weights and barbells (8, 10, 17), stacks of weight plates that permit variable resistance exercise (4, 6, 7, 16), and cam and pulley devices that emphasize multiple

repetitions consisting of both concentric and eccentric muscle contractions performed to "momentary muscular failure" (9,11).

Recently, exercise machines have been developed that incorporate hydraulic cylinders to provide both variable speed and variable resistance (Hydra-Fitness Industries, Belton, TX). An important design feature of this equipment permits concentric-only maximal-effort exercise for the agonist and antagonist muscle groups during each repetition of a particular movement. When the machines are placed in typical circuit fashion, this type of resistance training is similar in function to traditional circuit weight training (3, 6). In conventional circuit training, the weight overload is usually set at 40-70% of maximum lift capability. For hydraulic resistance exercise, the individual attempts to exert maximum muscular force against a level arm throughout the complete range of motion in both directions of the movement. The nature of such "all-out" repetitive contractions during a given bout of exercise should significantly augment heart rate and metabolic response.

The present study is the first to evaluate individual differences in acute heart rate responses and measures of gas exchange for a 3-station, hydraulic resistive exercise machine. Because the magnitude of the heart rate and metabolic response depends to a large extent on exercise intensity, the reproducibility of maximum repetition number was determined during multiple bouts of chest, shoulder, and leg exercise. In addition, we have compared the absolute and relative energy expenditure of the hydraulic exercises with published data on other forms of resistance exercise.

METHODS

Subjects. Table 1 presents the descriptive characteristics for the 20 male subjects. They were college students at the University of Massachusetts, Amherst, with no prior experience in a supervised program of weight training or weight lifting. Subjects received medical clearance from the University Health Services and signed an informed consent document in accord with University Human Subjects Review Guidelines.

Figure 1 – Subject performing chest exercise on the single-unit, 3-station hydraulic exercise apparatus.

Test apparatus. Figure 1 illustrates the exercise apparatus. On this device, there are three hydraulic cylinders; each is attached to its own layer system that provides concentric reciprocal movement primarily for the arms (chest press-chest row), arms and shoulders (shoulder press-lat pull), and legs (quadriceps extension-hamstring flexion).

Description of exercises. One of the experimenters demonstrated proper form and technique for each exercise according to guidelines specified by the manufacturer. The seat belt attachment on the machine was fastened around the waist to minimize extraneous movements. Resistance to movement can be regulated by selecting one of six speed settings from a dial on the machine. These settings correspond to six orifice sizes through which hydraulic fluid passes. The diameters of the orifices vary from 0.076 mm (setting 1) to 0.031 mm (setting 6). The dial setting for each exercise in the present study was 3 (0.076 mm orifice for CE and SE and 0.062 mm for LE). The exercises were performed as follows:

Chest exercise (CE). At the start of CE, the handles of the lever arm are held as close as possible to the axillary region just in front of the chest. The back and head remain in contact with the machine's upper body support. The handles are then moved forward as rapidly and forcefully as possible until a full extension position is achieved; the arms are then moved back to the starting position in similar fashion during the flexion phase of the movement.

Shoulder exercise (SE). At the start of SE, the handles of the lever arm are held at shoulder height. The arms are then thrust forcibly upward to full extension and then pulled down with maximal force to the starting position. The head and back are kept in contact with the upper body support.

Leg exercise (LE). At the start of LE, the arms hang vertically and grasp the underside of the bench to help secure the body to the machine. The head and back remain in contact with the upper body support. The ankles of both legs fit between ankle pads, with care taken to position the middle of the knee in line with the pivot of the lever arm. To initiate movement, both legs are fully extended with maximum effort from an initial angular position at the knee of approximately 90° and then flexed with maximum effort back to the starting position.

Each subject performed the maximum number of repetitions possible within a 20-s time interval. To count as one complete repetition, the exercise had to be performed as specified in the instructions. Repetitions were determined by visual observation for all exercises. During SE, a microswitch attached to the lever arm verified the visual count. There were never any discrepancies between the visual and microswitch counts.

Sequence of testing. Subjects were tested on four different days; days 1 and 2 were for assessment of body composition and max VO2, respectively. On the remaining two days, subjects performed three bouts of CE, SE, or LE, with the sequence of performing exercises on the first day balanced across subjects. Body weight was measured on each, day prior to testing. During the final 2 min of a 12-min rest period on the exercise apparatus, heart rate (HR) and gas exchange measurements (VO2, VCO2, VE) were obtained. Subjects then performed

a given bout of exercise for 20 s followed by a 20-s rest interval. This sequence of 20 s exercise, 20 s rest was repeated three times for each of the exercise stations. There was a 5- min rest (no exercise) until the next series of three exercise-bouts was performed. Subjects were instructed to perform maximally ("all out") for each repetition on all exercises. Strong verbal encouragement was given to exhort sub-jects to exert maximum muscular effort on each repetition.

Max VO2 test. Max VO2 was assessed on a Monark cycle ergometer. Pedalling rate was 60 rpm paced by a calibrated auditory-visual metronome; pedal rpms were counted electronically from a microswitch mounted on the pedal crank. Initial resistance was 1 kp for the first 2 min and 2 kp for the next 2 min. Thereafter, it was increased by 0.5 kp for each succeeding 3-min interval until subjects would no longer continue. This protocol is essentially the same as that described in a prior report (13). To compute max VO2, a plot was made of VO2 in relation to the actual work performed. The highest of two successive pairs of VO2 scores were averaged and designated max VO2. For all subjects, this occurred within the last 3 min of the test, even though pedal rpm and, thus, work rate usually declined during the last minute or two of performance.

Gas-exchange measurements. Metabolic measurements were determined by open circuit spirometry with an aliquot bag system for collection of expired air. Subjects breathed through a Rudolph high-velocity, low-resistance valve. Gas samples were collected for 40 s during each exercise/rest bout and expressed on a per-min basis. Expired air was also sampled during minute 5 of the 5-min rest interval between bouts. Expired gas volume was measured electronically as it passed through a turbine transducer into a mixing chamber. The flow transducer generated electronic pulses that were counted and displayed on a digital readout. The transducer was calibrated manually by forcing successive 3-1 aliquots through it from a calibrated 3-1 syringe at both steady (slow) and pulsatile (fast) flow rates that ranged from 3 to 70 1 for 30-s intervals. A 120-1 Tissot gasometer was used as the criterion measure to calibrate the transducer by having expired air pass in series from the Tissot through the transducer while a subject ran on a treadmill for 1-h periods at 0° grade and at different incline levels.

For gas analysis, the fractional concentration of the expired air samples were analyzed for 02 and CO2 by use of Applied Electrochemistry O2 and CO2 analyzers. Both analyzers were calibrated before and following each test with commercially prepared gas mixtures verified by the micro-Scholander technique. Energy expenditure was calculated for each interval as

kcal .min-1 = VO2 (1 .min-1) x caloric equivalent per 1 O2 at the given R (14). For R-values that exceeded 1.0, the caloric equivalent per 1 oxygen at an R of 1.0 was used.

Heart rate (HR; beats .min-1). A standard three-lead ECG and strip chart recorder were used to monitor HR continuously during all bouts of hydraulic exercise and the max VO2 test. For the analysis, HR was calculated from the last 6 beats of each 20-s bout of hydraulic exercise and the last 5 s of each minute during the max VO2 test.

RESULTS

Reliability of repetition number (repN)

To examine the metabolic and cardiovascular response of the three resistive exercises where work time during the performance was held constant, the stability of individual differences was determined for the number of repetitions performed for each exercise. Table 2 shows that the between-day reliability for repN, averaged across bouts for each exercise, was r = 0.76 for

LE, r = 0.87 for CE, and r = 0.89 for SE. There were no significant differences between days for corresponding bouts of each exercise (P > 0.05). However, repN performed for each exercise (using the average of test and retest), declined slightly across bouts 1 to 3; 1.1 reps (5.7%) during LE, 2.4 reps (11 %) during CE, and 2.5 reps (13.9%) during SE.

Reliability of gas exchange measures and heart rate

Oxygen uptake (VO2, 1. min-1. The results in Table 3 illustrate that reliability for VO2 ranged from r = 0.41 to 0.69 for individual bouts across exercises. For each exercise, the average reliability across bouts was r 0.52 for LE and r = 0.58 for CE and SE.

A repeated measures ANOVA (days x bouts x exercise) revealed that for each exercise, there were significant increases in VO2 between successive bouts of each exercise (F = 216.9; P < 0.05). For the exercise x bout interaction (F = 5.49; P < 0.05), a Tukey post-hoc multiple range test showed that VO2 LE and CE (bout 1) were not significantly different. All other between exercise comparisons of VO2 for all bouts and exercises were significantly different at P < 0.05. In most cases, LE elicited the highest VO2 response followed by CE and SE.

Heart rate (beats/min). The reliability coefficients for HR averaged across bouts was r = 0.80 for legs and r = 0.79 for chest and shoulders. With the exception of chest exercise, reliability and, hence, individual differences increased from bout 1 to bout 3 as a function of increasing heart rate. The results of the repeated measures ANOVA showed that the differences in HR between successive exercise bouts were significant for all exercises (P < 0.05). The magnitude of the increase in HR from bout 1 to 3 was fairly similar; 12.9 bpm (9.0%) for legs, 10.7 bpm (7.4%) for chest, and 13.2 bpm (9.5%) for shoulders. There were no significant differences in HR between corresponding bouts of the three exercises (exercise x bout interaction; F = 0.34). Reliability was higher for HR on each exercise (averaged across bouts) compared to the measures of gas exchange.

DISCUSSION

In this experiment, individuals were asked to perform maximally at one of 6 pre-set resistance settings throughout the range of movement for each repetition. However, there was no way to quantify the total amount of work or power accomplished. The external gauges mounted at eye level did provide immediate visual feedback of force exerted, but these gauges were not useful for quantitative assessment. Thus, any inconsistency in repN or exercise effort could produce low reliability for heart rate and metabolic response, as well as significant differences in the aboslute scores for these variables. In the present study, it was encouraging that reliability for repN ranged from r = 0.68 to r = 0.93, since fluctuation in maximal effort exercise could have markedly affected concomitant measures of heart rate and gas exchange.

For VO2, reliability coefficients ranged from r = 0.41 to r = 0.69; for heart rate, reliability ranged from r = 0.72 to r = 0.89. These results show that the acute VO2 and heart rate responses were consistently stable across days. These findings for VO2 are in contrast to data of Wilmore et al. (19), who reported that reliability for VO2 and kcal ranged from r = 0.20 to r=0.70. The low coefficients were ascribed to decreased interindividual differences in VO2 expressed relative to body weight, rather than unstable measurements during circuit exercise.

The peak VO2 measured during the three hydraulic exercises were 2.10, 1.87, and 1.78 1. min-1 for LE, CE, and SE, respectively. For comparison purposes with the data of others, oxygen consumption and heart rate were expressed relative to maximal values on the cycle ergometer test. For LE, V02 was 57.4%; for CE, it was 51.9%; and V02 for SE was 49.2%. Heart rate was highest during LE (85.4%), followed by heart rate during CE (85.2%) and SE (83.2%). Thus, it can be stated that subjects performed exercise at an average heart rate of 84.6% of HR max, at a corresponding average VO2 of 52.8% of the max VO2. McArdle and Foglia (12) reported that V02 ranged from 0.43 1. min-1 to 0.59 1.min-1 during one set of 8 reps for the 2- arm curl, arm and back press, and squat free weight and isometric exercises. Post-exercise VO2 was higher during the first minute of recovery (0.84 to 1.271 .min-1) compared to exercise. In terms of energy cost, the peak metabolic intensity was approximately 6

kcal .min-1. The highest heart rate occurred during the 2-arm press (134 beats/min or approximately 69% of maximum heart rate using an age-predicted maximum heart rate of 195). Byrd and Barton (2) reported that novice weight lifters had heart rates that averaged 145 beats/min after a 1-h workout, while the heart rate of experienced lifters averaged 152 beats/min.

Wilmore et al. (18) reported that 30 s of circuit exercise performed by men and women on Universal Gym equipment for three circuits of 10 exercises (performed at 40% of 1 RM) required 70% of max HR and 45% or less of max V02. For circuit exercise performed by five men at 7 stations using Cybex isokinetic equipment at slow speed (60°/s) and fast speed (120°/s) for 3 circuits, 12 reps/set and 30-s interval between sets, heart rate averaged 69% of max HR, and VO2, averaged throughout exercise, was 49% of max VO2 (3). Energy expenditure, computed in the same manner as in this study, averaged 9.6 and 9.9 kcal .min-1 for slow and fast speed circuits, respectively.

A recent study by Hempel and Wells (9) evaluated the energy expenditure of circuit exercise using Nautilus equipment. For the 16 male subjects, VO2 corresponded to 35.9% of max VO2, and heart rate averaged 71.7% of max heart rate.

Table 4 compares the pertinent data of the present study with results from the literature that have evaluated various forms of resistance exercise relative to heart rate and metabolic response. These comparisons show that the three exercises performed on the hydraulic equipment produce greater metabolic and heart rate responses than exercise performed isometrically and with free weights (12) or typical circuit exercise work-outs on Universal Gym (19) or Nautilus equipment (9, 11). This is true even when the average response based on the three exercises is used as the frame of comparison.

The caloric expenditure for the three hydraulic exercises averaged 37.7 Id (9.0 kcal .min-1); this is approximately 35% higher than exercise with free weights (12), 29.4% greater than the average kJ based on two studies using Nautilus (9, 11), and 11.5% higher kcal than circuit exercise with Universal equipment (19). The energy expenditure values in the present study averaged 8.9% less than slow and fast speed isokinetic circuit exercise (3). It seems reasonable that differences in kcal (and associated physiological measurements) between the present results and other studies of circuit exercise are due in part to methodological differences. We

have reported values associated with each bout of exercise (and the average) in contrast to an average value determined throughout circuit exercise.

Although the reliability of individual differences in work performance (reps) was only moderate, it was high enough to provide for consistency across days in the physiological response to maximal effort exercise. The use of on-line analog to digital devices interfaced with a microcomputer would provide two important advances with this type of equipment: (1) feedback to the user regarding effort (e.g., time to peak effort, average work and power, total work and power, and work and power expressed relative to range of motion), and (2) quantification for precise evaluation and comparison with other modalities of resistance exercise.

The results of the present study demonstrate that exercise performed on a 3-station hydraulic resistance apparatus produces reliable individual differences in repN, heart rate, and associated respiratory gas measurements. The magnitude of the average heart rate and metabolic response patterns with maximal effort hydraulic exercise is in the range recommended by the American College of Sports Medicine to promote improvements in cardiorespiratory fitness (1). When energy expenditure is expressed in the MET classification scheme for defining exercise intensity, the MET level averages approximately 7.5, which would be considered heavy intensity exercise.

A description of the Total Power apparatus is available from the manufacturers: Hydra-Fitness Industries, 2121 Industrial Park Road, Belton, TX 76513. This study was supported by a grant from Hydra-Fitness Industries to the Department of Exercise Science, University of Massachusetts, Amherst, MA.

The authors thank Maureen Rafflo for her technical assistance. Frank I. Katch and Patty S. Freedson are Fellows of the American College of Sports Medicine.

Present address for Carole A. Jones: Mt. Sinai Hospital, Hartford, CT.

REFERENCES

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  3. GETTMAN,L.Theaerobiccostofisokineticslowandfastspeedcircuittraining programs. Abstracts of Research Papers. Washington, DC: American Association, Health, Physical Education, Recreation, and Dance, 1978, p. 31.

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  6. GETTMAN,L.R.,L.A.COLTER,andT.A.STRATFIMAN.Physiologicchangesafter20 weeks of isotonic vs isokinetic circuit training. J. Med. Phys. Fitness. 20:265-274, 1980.

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Effects of hydraulic circuit training on cardiovascular function

Effects of hydraulic circuit training on cardiovascular function

HAENNEL, R., K.-K. TEO, A. QUINNEY, and T. KAPPAGODA. Effects of hydraulic circuit training on cardiovascular function. Med. Sci. Sports Exerc., Vol. 21, No. 5, pp. 605-612, 1989. The effect of hydraulic circuit training (HCT) on cardiovascular (CV) function was assessed in 32 healthy middle-aged males (X age = 42.2 ± 2.1 yr). Maximal aerobic power (VO2max), with simultaneous measurement of stroke volume (SV) and cardiac output (CO), by impedance cardiography, was assessed pre- and post-training. Subjects were randomly assigned to a nonexercising control group, a cycle training group (cycle), or one of the two HCT groups. Training groups participated in a 9 wk program, 3 d . wk-1. Subjects assigned to HCT exercised on a 9 station circuit, completing 3 circuits . d-1. Each circuit consisted of three 20 s work intervals at each station with a 1:1 work:rest ratio. One HCT group (HCTmax) completed the maximal repetitions possible (RM) during each work interval. The other HCT group (HCTsub) exercised at 70-85% of RM. Following training VO2max (m1 0 kg-1min-1) was significantly increased in all training groups (18.0, 12.5, and 11.3% for cycle, HCTsub, and HCTmax groups, respectively; P < 0.05). The increase in VO2max observed in the cycle group was significantly greater than that recorded by the two HCT groups (P < 0.05). For all three training groups, the increase in VO2max was associated with increases in SVmax and COmax (P < 0.05 for both). These findings suggest that both maximal and submaximal HCT programs can elicit improvements in cardiovascular fitness.

PHYSICAL TRAINING, OXYGEN UPTAKE, WEIGHT TRAINING, HYDRAULIC CIRCUIT TRAINING, EXERTION, CARDIAC OUTPUT

Circuit weight training (CWT) is a form of strength training in which a series of exercises are performed using resistance equipment in a predetermined sequence. In most CWT programs, 8 to 12 different exercises are performed, usually at an intensity equivalent to 40-60% of the maximum force generated by the participating muscles (10). Short work bouts incorporating 10-20 repetitions of each exercise are alternated with periods of rest, during which time the individual moves from one station to another. Although there is little doubt that CWT

improves muscular strength and endurance (2, 9, 20), its overall effect upon the cardiovascular system remains controversial. Several investigators (11, 20) have reported small but significant improvements in maximal aerobic power, as assessed by treadmill tests and bicycle ergometry, after CWT. Others have failed to confirm such an effect (2, 13). Further, it has been reported that the heart rate response to submaximal exercise on a bicycle ergometer (2) or a treadmill (13) is unchanged following CWT.

These differences in the effects of CWT on cardio-vascular fitness could be attributed to the relative intensity of exercise used in the programs (10, 20). For in-stance, the intensity of exercise may be inadequate to achieve certain hypothetical targets for heart rate and aerobic demand for enhancing maximal aerobic power (12, 13) (see Discussion).

One possible method of circumventing this problem is to use devices that provide accommodating resistance from variable hydraulic cylinders in the circuit training program. It is suggested that such devices allow high intensity concentric exercise for both the agonist and antagonist muscle groups, thus creating both the metabolic and cardiovascular demands necessary for the enhancement of maximal aerobic power (15). The purpose of the present study is to determine whether the changes in maximal aerobic power, cardiac output, and stroke volume induced by hydraulic circuit training (HCT) were comparable to those induced by a conventional program of bicycle training.

METHODS

Subject selection. Thirty-two male volunteers participated in this study. The subjects were instructed as to the nature of the study, and written informed consent was obtained. Before training, a medical history, physical examination, resting ECG, and graded exercise test (GXT) on a bicycle ergometer were performed. None of the subjects had clinical evidence of heart disease. The subjects were assigned to one of the following groups (N = 8 in each); 1) a nonexercising group (control); 2) an HCT group, which completed the maximum number of repetitions possible during each work interval (HCTmax); 3) an HCT group, which completed 70-85% of the maximum number of repetitions possible during each work interval (HCTsub); and a group which participated in a dynamic exercise training program on bicycle ergometers (cycle).

Measurement of maximal aerobic power. Maximal aerobic power was assessed by measuring the oxygen uptake (VO2max) achieved during a GXT on a bicycle ergometer (model 740, Siemens Electric Ltd.). The initial workload was set at 20 W. At 3 min intervals it was increased successively to 30, 50, and 80 W, and in steps of 50 W thereafter. For both the pre- and post-assessments the exercise test continued until one of the following end points was attained: a plateau, or decrease in VO2 with increasing workloads; attainment of 95% age predicted maximal heart rate; or volitional exhaustion (defined as a Borg scale reading >18 or an inability to maintain the cycling velocity of 60 rpm). The VO, was measured at each workload using a continuous flow technique (1). The peak VO, value obtained during the exercise test was recorded as VO2max.

Measurement of cardiac output. Stroke volume (SV), cardiac output (CO), and heart rate (HR) were measured by impedance cardiography (Minnesota Impedance Cardiograph, model 304A, Surcom, Inc.). Use of this technique has been validated in this laboratory for endurance trained young male subjects and cardiac patients, both at rest and during exercise (19).

Recordings were made at rest and immediately (within 3 s) upon completion of each workload during the exercise test. During the measurements, subjects were required to hold their

breath at normal end-expiration to avoid artifact due to respiratory movement. The average of five cardiac cycles was used in the calculation of SV.

Blood pressure was measured using a mercury sphyg-momanometer during the second minute of each stage of the GXT. Mean arterial pressure (mm Hg) was calculated as the diastolic blood pressure ± 1/3 pulse pressure.

Training program. All subjects assigned to training exercises 27 min . d-1, three times a week for a 9 wk period. Each training session was preceded by a 5 min warm-up and followed by a 5 min cool-down period. The dynamic training group (cycle) exercised on bicycle ergometers for 27 min at a workload that corresponded to 70-85% of their heart rate reserve (14). The resting heart rate for this calculation was recorded following 15 min of quiet rest in the seated position before the pre-training GXT.

Subjects assigned to HCT exercised on nine discrete work stations of variable resistance hydraulic equipment (Hydra-Fitness Canada Ltd). The following movement patterns were used: knee extension and flex-ion; hip extension and flexion; elbow extension and flexion; shoulder extension and flexion; and planter flexion. A list of the various exercise stations incorporated into the circuit is presented in Table 1. Over the 2 wk immediately preceding training the subjects assigned to HCT were familiarized with the equipment and the training circuit. Stations were arranged so as to exercise the upper and lower body alternately whenever possible. The circuit consisted of three 20 s work intervals at each station with a 1:1 work:rest ratio. The first two work intervals were followed by 20 s rest intervals, and the third work interval was followed by an 80 s rest period to allow time for moving from one station to the next.

One HCT group (HCTmax) was asked to complete the maximum number of repetitions possible during each work interval. The initial cylinder settings for the three successive work intervals were 1, 3, and 2. However, throughout the training program, the valve settings were adjusted so that the subjects could not exceed a work rate greater than one repetition . s-1 (16).

Values reported represent the mean values achieved for a given exercise over the three work intervals. Values in parentheses represent the average valve settings and repetitions achieved in the first 3 wk of training.

* Significant difference between the two HCT groups (P < 0.05).

The second HCT group (HCTsub) had an initial assessment similar to that undertaken by the HCTmax group. The training intensity for the HCTsub group was set in a manner that permitted completion of 70-85% of the maximum repetitions possible for a particular valve setting. The number of repetitions completed during each work interval was controlled by having the subjects exercise to a set cadence. For the HCTsub group the maximum repetitions for each 20 s work interval was established before training and was reassessed at the end of the 3rd and 6th wk of the program. The adjusted programs were used for the subsequent weeks of training.

The average repetitions completed by both HCT groups during the initial 3 and final 3 wk of training are presented in Tables 1 and 2, respectively. Over the course of the study, the peak torque and work completed during one lower and one upper extremity exercise was measured using a Cybex II isokinetic system. This study was undertaken to monitor the changes in muscular strength resulting from the training programs. The improvements in peak torque and work in the HCTmax and HCTsub groups were similar over the period of study. [These findings are available in a Ph.D. dissertation at the University of Alberta (R. H. Haennel).]

Values reported represent the mean values achieved for a given exercise over the three work intervals.

* Significant difference (P < 0.05) between the HCTsub and HCTmax groups.

Acute response to training sessions. The HR and blood pressure was monitored daily, before exercise and in response to the various training regimes. The HR was monitored with Sport Testers (models pe 2000, and pe 3000; Polar/electro Ltd.). The blood pressure response to training was assessed using an electronic sphygmomanometer (Infrasonde, model D4000, Puri- tan-Bennett Canada Ltd). For the cycle training group HR and blood pressure were measured during steady state exercise. For the HCT groups, the HR response was recorded at the end of each work and rest interval. It is emphasised that for the HCT training groups, the heart rates were not measured during a steady state session. The blood pressure response was assessed during completion of the bilateral knee extension/flexion exercise. The rate pressure product was calculated using both the HR and blood pressure responses to the bilateral knee extension/flexion exercise.

Statistical analysis. Group data presented are ex-pressed as means ± SEM. A comparison of pre-training measurements was made using a two-way analysis of variance to assess discrepancies between groups (18). The effects of training in each group were assessed by a two-way analysis of variance of the post-training data. The magnitude of the changes produced by training in the four groups was compared by an analysis of variance on the difference (pre- and post-training). A probability level of P < 0.05 was accepted as the minimum value for statistical significance between groups. For a given variable, if a significant F value was obtained, a test of least significant difference was performed to assess the significance of the specific differences among the mean values.

In circumstances in which there were differences in the base-line data related to certain discrete variables (e.g., heart rate), an additional analysis of covariance was performed to confirm the existence of a training effect.

RESULTS

The study was completed on 32 middle-aged males. Mean values for their physical characteristics were: age 42.2 ± 2.1 yr; height 178.6 ± 2.4 cm; and weight 83.2 ± 4.2 kg. The VO2max for the entire sample, assessed by bicycle ergometry, was 32.4 ± 1.6 ml . kg-1 . min-1. There were no significant differences among the four groups for any of these variables. The cardiac output and VO, values at rest were not significantly different in the four groups in the pre-training state. The average heart rate in the HCTsub group was significantly higher, with a corresponding "downward" adjustment in stroke volume (Table 3). Body weight did not change significantly over the course of the study.

Acute Cardiovascular Response during the Training Sessions

Mean HR responses during training sessions in the HCTsub and HCTmax groups were significantly lower than those recorded in the cycle training group (P < 0.05). Diastolic blood pressure recorded during the training sessions was significantly higher in the HCTmax than for either the cycle or HCTsub, training groups (P < 0.05). Rate pressure product, calculated from the training HR and SBP data, was significantly lower for the HCT groups than in the cycle trained group (P < 0.05). These observations are summarized in Table 4.

Responses of the Cardiovascular System to Training

Rest. Following training, the resting HR was reduced significantly in the HCTsub group (P < 0.05). Both the cycling and HCTsub groups demonstrated significant increases in SV (P < 0.05). Mean arterial pressure was unchanged in the three training groups. These data are summarized in Table 3.

* Significant difference between pre- and post-training data (P < 0.05).

Submaximal exercise. Following training, there was a significant reduction in the HR responses to exercise in the cycling and HCTsub groups. Because there were small differences in the pre-training HRs at rest (Table 3), an analysis of covariance was used to compare the pre- and post-training regression lines related HR to load. In these two training groups, the elevations of the regression lines, as indicated by the adjusted means (18), were significantly reduced by training (cycle: F = 21.1, P < 0.01; HCTsub: F = 28.2, P < 0.01). Corresponding differences were not observed in the control group and in the HCTmax group (control: F = 0.31, P > 0.05; HCTmax: F = 2.41, P > 0.05) (Fig. 1).

For the cycling and HCTsub groups, the reduction in HR was associated with an increase in SV at corresponding values of HR. This effect was not evident in the control group or in the HCTmax group (Fig. 2).

Maximal exercise. Following training, VO2max (Table 5) was significantly increased in all training groups (P < 0.05). There was no significant change in the control group. The increment in maximal aerobic power observed in the cycle training group was significantly greater than that observed in both HCT groups (P < 0.05). Maximum HR was unchanged in all four groups, but there was a significant increase in maximum SV in the three training groups (P < 0.05). Thus, the maximal CO was increased significantly in all three training groups (P < 0.05). At maximal exercise there were no significant changes in mean arterial pressure (Table 5).

TABLE 4. Overall mean HR, blood pressure, and rate pressure responses to the training programs averaged over the 9 wk.

Values are expressed as means ± SEM. Values with a similar suffix (a, b, c, d, or ab) are not significantly different (P > 0.05). HR = heart rate (beats . min-1); SBP = systolic blood pressure (mm Hg); DBP = diastolic blood pressure (mm Hg); RPP = rate pressure product (HR x SBP x 10-2). For the HCT groups, RPP was calculated using the HR and SBP response to the bilateral knee exercise. % HRmax reserve = [(exercise HR - rest HR)/(HRmax- rest HR)] x 100.

DISCUSSION

The present study was undertaken to determine the effect of HCT on the cardiovascular system of previously untrained middle-aged adult males and to compare these effects with those induced by a conventional program of cycle training. The main responses of the cardiovascular system to HCT included a significant increase in VO2max maximal SV, and maximal CO.

Figure 1—Regression lines relating HR (y) to workload (x) for the four groups before (—) and after (---) training. Top left, control group: (--) y = 0.42(x) + 73.4; (---) y = 0.46(x) + 71.2. Top

right, cycle group: (—) y = 0.43(x) + 73.4; (---) y = 0.40(x) + 64.2. Bottom left, HCTsub group: (—) y = 0.44(x) + 80.5; (---) y = 0.42(x) + 71.2. Bottom right, HCTmax group: (—) y = 0.44(x) + 72.3; (---) y = 0.42(s) + 67.4.

Effects of Training on the Cardiovascular Responses to Submaximal Exercise

The cardiovascular adaptations to submaximal exercise were assessed at all workloads. Following training, HR was reduced at all submaximal workloads in both the HCTsub and the cycling groups (Fig. 2). This response, a classical cardiovascular adaptation to exercise training, has been attributed to a combination of increased parasympathetic tone and diminished sympathetic activity (6, 17).

The pre-training HR/SV profiles for the four groups were characterized by an increase in SV from the resting state through to a maximum value, which was achieved at a HR between 120-130 beats.min-1. This peak SV was maintained through to maximal HRs and workloads. These observations are similar to previously published data for untrained middle-aged males (4). Following training, the HR/SV profiles of the HCTsub and cycling groups were altered, such that for a given HR there was an increase in SV (Fig. 2). although this relative increase in SV is likely to be a consequence of an increase in ventricular volume, a change in myocardial contractility cannot be excluded (6). In the HCTmax group an increase in SV was evident only at high HRs (and workloads).

Effect of Training on the Cardiovascular Responses to Maximal Exercise

There is no general agreement on the effects of CWT on cardiovascular responses to maximal exercise. These differences, which are particularly evident in the changes in VO2max (2,8,11,13,20), have been attributed either to differences in training protocols (10) or to characteristics of the population examined (20). In the present study VO2max increased by 12.5 and 11.3% in the HCTsub and HCTmax groups, respectively. The increase in VO2max observed in the cycle training group (18.0%) was greater than that observed in both HCT groups (P < 0.05).

Figure 2-Mean heart rate/stroke volume profile of the four groups; pre (●)- and post (!)- training. For each group the points represent the coordinates of the mean heart rate/stroke volume responses to the particular workload during the GXT. The data presented are limited to those workloads which all the subjects in each group completed. The maximal SV is increased in all three exercising groups following training.

TABLE 5. Cardiovascular responses at maximal exercise on a bicycle ergometer.

(ml.beat-1); CO = cardiac output (1.min-1); MAP = mean arterial pressure (mm Hg); RPP = rate pressure product (HR x SBP x 10-2). Values with a similar suffix (a, b, c, d, (ml.beat-1); CO = cardiac output (I. min-1); MAP = mean arterial pressure (mm Hg); RPP = rate pressure product (HR x SBP x 10-2). Values with a similar suffix (a, b, c, d, e, f, etc.) are not significantly different (P > 0.05).

One explanation for this difference may relate to the "specificity principle," whereby the changes induced by physical training are specific to the muscles involved and to the pattern in which they are used during training (7). Thus, using a bicycle ergometer to compare the effects of cycle training with HCT would bias the results in favor of cycle training. However, the influence of the specificity principle was assessed by Gettman and Pollock (10), who used arm ergometry to estimate the effects of CWT and dynamic exercise training. The changes induced by the training programs were evident even in the nonspecific tests.

The aerobic demand imposed by the two modes of exercise may be an additional factor contributing to the differences in the magnitude of the increase in VO2max in the cycle trained and HCT groups. At half of the stations in the HCT programs the muscle mass involved (arms) was smaller than that used in cycling. It has been shown that the oxygen cost of arm work is approximately 70% of leg work at comparable heart rates (7,20). Therefore, it is likely that the overall stimulus for aerobic improvement may have been less for HCT than for cycle training.

The similarity in the improvement in VO2max for the two HCT groups merits scrutiny. There are two aspects of any training program that have a bearing upon the improvement in VO2max,

i.e., the metabolic demand imposed by the training schedule and the heart rate response to the program. In the absence of a direct measurement of the oxygen cost of the HCT programs, an indirect assessment could be made using an index derived by multiplying the valve settings by the repetitions. On this basis one might infer from the data in Tables 1 and 2 that the HCTmax, group had a greater metabolic demand than the HCTsub group. However, the findings of Ballor et al. (5), who measured the metabolic demand associated with maximum hydraulic resistance exercise, suggest that such a simple index does not correlate with the oxygen cost of the activity. Although the study reported by Ballor et al. (5) was done on an apparatus not identical to the Hydra Gym used in the present study, both systems incorporated the same fundamental principles. Thus, it is suggested that, because the improvements in VO2max observed in the two HCT groups were similar, the cummulative metabolic demand of the two programs was also similar. However, in the absence of direct measurements, this contention remains speculative.

With respect to HR, the threshold intensity necessary to produce a training effect on the cardiovascular system has been reported to be approximately 60% of the heart rate reserve (3). On the basis of this calculation using the pre-training GXT, the HCTsub and HCTmax groups were required to maintain HRs greater than 134 and 129 beats.min-1, respectively. In these two groups, the respective HR responses during the training sessions averaged 60 and 75% of HR reserve. These findings suggest that the magnitude of the HR responses to the two HCT programs are adequate for improving VO2max. However, it is necessary to emphasize a note of caution in making extrapolations of this nature. HCT, unlike a continuous dynamic activity such as cycling, involves "non-steady state" exercise. Thus, comparisons of calculated training intensities based upon the cardiovascular responses such as HR are likely to be spurious when fundamentally different forms of exercise are being considered.

The findings of the present study lend support to this view. The HR response to the training sessions involving HCTmax met the conventional criteria for the threshold intensity necessary to induce training effects, as did the cycling group. However, unlike the cycling group, which demonstrated a reduction in HR during submaximal exercise, the HCTmax group failed to demonstrate a change in HR at submaximal workloads. The HCTsub group (which had a lower HR response during training) responded in a manner similar to the cycle training group with respect to the HR response to submaximal workloads. Clearly, considerations other than HR during training sessions play a role in the cardiovascular adaptation to training.

Present findings may have some practical implications. The fact that the improvement in VO2max observed in the HCTsub group was similar to that seen in the HCTmax group suggests that HCT at less than the maximal effort can be used to enhance cardiovascular fitness.

The authors wish to acknowledge the support of the MSI Foundation of Edmonton, the Imperial Order of the Daughters of the Empire (Edmonton Chapter), and Hydra-Fitness Canada Ltd.
Address for correspondence: Dr. Tissa Kappagoda, 2C244 Walter Mackenzie Center, University of Alberta, Edmonton, Alberta, Canada T6G 2R7.

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