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The purpose of the investigation was to determine the effect of exercise training intensity on the lactate and ventilatory thresholds in sedentary and in active subjects using meta-analysis procedures. The original analyses included 85 study groups from 34 studies. The dependent variable was oxygen consumption at the specified threshold, and the independent variables were training intensity (control and four intensities ranging from below threshold to near maximum) and fitness level (sedentary and conditioned). Data were analyzed statistically using methods described by Hedges and Olkin (13). The results showed that sedentary subjects (effect size (ES) = 2.32) improved significantly over controls (ES = 0.15), while conditioned subjects (ES = 0.63) showed nonsignificant gains. There were no significant differences among training intensities within the fitness categories (Sed ES = 1.6 - 3.1; Cond ES = 0.3 - 1.1) although the conditioned subjects tended to respond better to high intensity training (ES of 1.1 vs 0.4). It was concluded that training at an intensity near the lactate or ventilatory threshold is an adequate training stimulus for improving the thresholds for sedentary subjects, but a higher intensity may be necessary for conditioned subjects. Detraining will reduce lactate and ventilatory thresholds.

In order to determine whether exercise mode affects recovery energy expenditure, 7 active men (average age 25 yrs) performed a control rest and three submaximal exercise bouts in counterbalanced order in separate weeks. The bouts, designed to involve three levels of eccentric muscular activity, included 60% [Formula: see text] jog (60 J), 60% downhill (−5%) jog (60 DH), 60% cycling (60 C), and a control session. Following a 24-hr period of regulated activity and diet, subjects exercised for 60 min. [Formula: see text] and RER were assessed during 48 hrs of regulated recovery. Total energy use was elevated following 60 C and 60 DH versus control, and fat energy use was elevated following 60 J, 60 DH, and 60 C versus control. For combined trials, the total energy use was higher at 1, 2, and 9 hrs postexercise. These results do not support the hypothesis that eccentric muscular activity affects the magnitude of recovery energy expenditure. Key words: energy expenditure, fat energy expenditure, excess postexercise oxygen consumption, exercise mode

In order to compare the physiological and psychological responses to various levels of eccentric exercise, 7 active men (25 ± 5 yrs) exercised for 60 min on separate days at 60% of apparatus specific [Formula: see text] max using downhill jogging (−5% 60DH), level jogging (60J), and cycling (60C). Virtually all of the responses to 60DH fell between 60J and 60C. Heart rate, O2 pulse, and respiratory exchange ratio were significantly different among modes, with the responses during 60DH falling between those during 60J and 60C. Fat energy expenditure during the 60-min exercise bout was significantly higher during 60J, followed by 60DH and then 60C. Ratings of perceived exertion followed the order of 60C > 60DH > 60J. Vigor and fatigue scores on the Profile of Mood States also followed a hierarchy that paralleled the physiological responses. These results suggest that downhill jogging elicits physiological and psychological responses that are between those elicited by level jogging and cycling. Key words: energy expenditure, fat energy expenditure, ratings of perceived exertion, eccentric contractions

Investigations on resting and recovery metab- olism have used both preexercise and separate control-day mea- surements as a baseline for comparisons. The purpose of this study was to compare preexercise resting data with nonexercise control-day resting data. Seven active men aged 25 ± 5 y and weighing 83.2 ± 15.4 kg followed prescribed dietary (12-h fast) and activity (48-h abstinence) preparatory protocols and were scheduled to exercise for 60 ruin on three separate occasions. A fourth session involved no exercise (control) and included an extended rest period. Resting metabolic rate (RMR) and heart rate measured in a semirecumbent position were not significantly different among preexercise and control conditions. Respiratory exchange ratio (RER) increased as the control rest was extended to 120 mm. Reliabilities for both RMR and RER were initially high but were decreased at the end of the extended rest. These results suggest that preexercise RMR data can be used as a base- line for comparison purposes. In addition, prolonging the rest period does not appear to improve the RMR or RER values. Am J Clin Nutr 1994;59:28-31.

During the 1980s, worksite health promotion and wellness education programs became increasingly prevalent in business and industry. A similar pattern currently is emerging among institutions of higher education. To assist in development of college and university programs, this article presents philosophy, delineates goals and objectives, and describes interventions applied and components included within the Missouri University Health Education and Lifestyle Promotion (H.E.L.P.) Program. Unlike most other college and university wellness efforts, the MU H.E.L.P. Program utilizes a carefully structured, “comprehensive package” approach. This article emphasizes benefits of networking existing campus resources and personnel and the importance of effective program design, implementation, and evaluation. The MUH.E.L.P. Program serves as an excellent example of how a multidisciplinary approach to employee health promotion and wellness education programming can be cost-effective, time-efficient, and highl...

The purpose of this investigation was to determine the effects of various crank arm lengths on oxygen consumption for trained cyclists. Secondary purposes were, if optimal crank arm lengths existed, to determine if these lengths could be predicted based on an individual's leg length. Six trained cyclists completed four experimental protocols riding at a workload of approximately 68% of [Formula: see text] using crank arm lengths of 165, 170, and 175 mm. During each protocol, the cadence, oxygen consumption, and distance traveled were determined, and values were combined to give a [Formula: see text] value. The values then were placed in either a high, medium, or low efficiency category. Significant differences were found among the three protocols. No significant correlations were found between each subject's most efficient crank arm length and leg length. The results of the study suggest that each subject has a most efficient crank arm length, but it does not appear that optimal crank arm length can be predicted by leg length. Key words: optimal crank arm length, leg length, efficiency

The purpose of the study was to develop an equation to predict the oxygen cost of cycle ergometry. Forty subjects performed an incremental cycle ergometer test on three occasions at 50, 70, or 90 rpm in a counterbalanced order. Work rate was incremented every 5 or 6 min when steady rate values were achieved. To ensure accurate work rates, ergometer resistance was calibrated and flywheel revolutions were electronically measured. Oxygen consumption was measured with a computer interfaced system which provided results every minute. Oxygen consumption (mL.min-1) was the dependent variable, and independent variables were work rate (WR in kgm.min-1), pedal rate (rpm), weight (Kg), and gender (males, 0; females, 1). The following nonlinear equation was selected; VO2 = 0.42.WR1.2 + 0.00061.rpm3 + 6.35.Wt + 0.1136.RPM50.WR-0.10144.RPM90-WR-52-Gender, R2 = 0.9961, Sy.x = 106 mL.min-1, where RPM50: 50 rpm = 1, and RPM90: 90 rpm = 1, else = 0. It was concluded that the oxygen cost of cycle ergometry is nonlinearly related to work rate and pedal rate, linearly related to weight, and that females use less oxygen for a particular work rate.

In order to compare responses on six modes of exercise for maximal oxygen consumption [Formula: see text] and ventilatory thresholds (VT-I, VT-2), 10 male recreational exercisers (23 ± 3 yrs) completed incremental maximal tests on treadmill, stationary skier, shuffle skier, stepper, stationary cycle, and rower. After extensive habituation, [Formula: see text], VT-1, and VT-2 were determined during each maximal bout. A MANOVA followed by ANOVAs, Tukey post hoc tests, and noncentral F tests indicated that the treadmill elicited a significantly higher peak oxygen consumption than did the other modes, and the skier and stepper values were higher than the rower. [Formula: see text] at VT-1 was higher on the treadmill than cycle. The treadmill also elicited a higher [Formula: see text] at VT-2 than the shuffle skier, cycle, and rower. However, no differences were observed among modes for VT-1 and VT-2 when expressed as a percentage of [Formula: see text]. These results suggest that the treadmill elicits a higher aerobic capacity measure than other modes, but the ventilatory threshold responses [Formula: see text] are similar among modes. Key words: exercise mode, aerobic capacity, lactate threshold

In order to compare the cardiovascular and perceived exertion responses to 6 modes of exercise, 10 male recreational exercisers were habituated to treadmill jogging, stationary skiing, shuffle skiing, stepping, stationary cycling, and stationary rowing. After following a specific dietary preparation, each participant performed a 20-min exercise bout at a constant 14-rating of perceived exertion (RPE) followed by a second exercise bout at 60% of mode-specific peak oxygen consumption (VO2peak). On the 14-RPE trial, oxygen consumption (VO2) and oxygen pulse were significantly higher during jogging than during other exercise modes, and oxygen pulse was higher during skiing than during shuffle skiing. On the 60% VO2peak bout, oxygen pulse was significantly higher during jogging than during shuffle skiing, cycling and rowing. Ratings of perceived exertion were significantly higher during cycling than during jogging. These results indicated that a variety of exercise modes can be used to develop fitness, but jogging may induce a slightly more favorable VO2-to-RPE relationship.

The purpose of the study was to compare the %VO2max versus %HRmax regression equations developed from data collected during incremental work on six exercise modes: treadmill (T), cycle (C), skier (S), shuffle skier (SS), stepper (ST), and rower (R). Ten active males were habituated to all modes and then performed an incremental test to maximum on each mode. Mode order was assigned by Latin square sequences and the tests were separated by at least 72 h. VO2 and HR were recorded at each increment. Regression analyses were performed using SAS-GLM. Regressions for T, S, SS, and ST were not significantly different. C had a lower intercept and higher slope, while R had a higher intercept and lower slope than the other exercise modes. These results suggest that weight bearing exercise modes have similar %VO2max-%HRmax regressions. However, weight supported and arm exercise modes appear to have different regressions.

This 1 year study examined the effect of high impact and low impact activities on bone mineral density (BMD) at the lumbar vertebrae (L2-L4) in healthy, sedentary, early postmenopausal women. Fifteen subjects whose postmenopausal status was verified by the blood levels of follicle stimulating hormone (FSH) and estradiol were chosen. These subjects were tested on the following variables: BMD via dual photon absorptiometry, heart rate response to the Balke treadmill test, percent fat via skinfolds, and a 3-d dietary analysis. Subjects were matched and then assigned randomly to one of three groups: (a) a control nonexercising group, (b) a low impact exercise group, and (c) a high impact exercise group. The control nonexercising group experienced a significant linear decrease in BMD during the study (F = 12.63, P = 0.002). Both the low and high impact exercise groups maintained BMD during the study (F = 0.04, P = 0.85; F = 1.08, P = 0.31, respectively). The difference in BMD between the low impact and the high impact exercise groups was not significant (F = 0.36, P = 0.55). In conclusion, 20 min of moderate intensity low impact or high impact exercise 3 d.wk-1 for 1 yr is effective in maintaining BMD in early postmenopausal women.

(1978). Changes in 40K Counts with Exercise. Research Quarterly. American Alliance for Health, Physical Education and Recreation: Vol. 49, No. 1, pp. 95-100.

Not much is known concerning the physiological performance capabilities of wheelchair confined populations. Further, the instrumentation to collect physiological data has not been available until recently. It is in the area of work capacity measurement of the handicapped that the arm ergometer is of greatest interest (particularly for those who have a functional loss of one or both legs). In recent years, there has been an attempt to develop instrumentation and investigate some of the physiological issues surrounding quantified exercise in wheelchair confined populations. The intent of this review is to provide the reader with an overview of the state of the art in wheelchair and wheelchair ergometric cardiorespiratory performance.

In brief: The calories expended and the substrates used by walking vs jogging were compared in nine young men who walked and jogged at 65% maximum heart rate (HR max) (about 125 beats· min(-1)) for 60 minutes and 75% HR max (about 145 beats· min(-1)) for 45 minutes. Jogging utilized more total energy and more fat energy than walking at both intensities. In addition, the men perceived jogging to be less strenuous, and oxygen pulse, an indicator of cardiovascular efficiency, was higher during jogging than walking. Recovery energy use was greatest after jogging at 75% HR max.

In order to examine the relationship between fatty acid distribution of skeletal muscle membranes and age, a needle biopsy was performed on the vastus lateralis muscle of 20 healthy, non-obese males, ranging in age from 22 to 73 years. The muscle sample was homogenized, centrifuged at 100,000 x g, and the resulting pellet was saponified and acidified. The fatty acids and cholesterol were removed by a single hexane extraction and analyzed by gas--liquid chromatography with flame ionization detection. All subjects regardless of age had no consistent differences in the fatty acid profiles and cholesterol composition in the tissue. Correlation coefficients indicated no significant relationship between the age of the individual and any of the analyzed lipids. The results of this study indicated that aging may not be reflected by gross changes in the composition of structural lipids in the cell.

In an attempt to reduce the confusion regarding reported effects of age upon maximal exercise heart rate (HR max), a comprehensive review of the English literature was conducted to obtain descriptive statistical data representing over 23,000 independent subjects from 5 to 81 years old. The data were split randomly into two data sets for independent regression analyses. HR max was the dependent variable while independent variables include: age, age2, age3, age4, sex, level of fitness, type of ergometer, exercise protocol, continent of residence, and race. After cross validation the data were pooled and reanalyzed. Additional validation was accomplished on identifiable subsets of the data, e.g., cross sectional, longitudinal, training, comparative ergometry, and comparative sex studies. Results identified negative linear and non-linear age factors, an ergometry factor, a fitness factor and a continent factor. Age accounted for about 70–75% of the variability. Generalized equations were proposed. Ev...

Twelve long-distance runners were evaluated by physical examination, electrocardiogram, vectorcardiogram, chest x-ray film, and echocardiogram; and the results were compared to the findings in 12 normal control subjects. The athletes showed a significantly higher frequency of gallop rhythms with a third or fourth heart sound. Electrocardiographic and vectorcardiographic abnormalities consisting of right or left ventricular hypertrophy, bradycardia, and alterations in the ST-T wave were also present in the runners. Echocardiographic examination of the athletes revealed increased wall thickness, left ventricular muscular mass, diastolic volume, and ventricular function. It is essential that the physician who examines athletes be aware of the spectrum of apparently abnormal findings in this group. Echocardiographic studies should prove useful in establishing the presence or absence of some forms of cardiac disease in athletes.

(1969). Principles of Stability: A Re-Examination. Research Quarterly. American Association for Health, Physical Education and Recreation: Vol. 40, No. 2, pp. 419-422.

Ten moderately well-conditioned male students at the University of Toledo ran on a treadmill, fully attired in football equipment, with an environmental temperature of 90 F and relative humidity of 70%. Each subject was partially acclimatized and then exposed to the experimental conditions on five consecutive days (balanced Latin square). Four 1-liter water replacement schedules (designed to test specific hypotheses), and a control of no water, served as five levels of the independent variable. Data were collected on rectal temperature, heart rate, pulse pressure, specific gravity changes for whole blood and for plasma, and sweat loss. Results showed that water ingestion early during the work session combated the effects of heat stress better than late administration; however, this advantage was reduced toward the end of the work session. The results were mixed concerning the relative merits of ingesting the water in one or two administrations.

High school males (N = 28) were divided into two groups, equated on intelligence, and then trained for play recognition from the defensive end position in football. Motion pictures were used with one group and flash cards were used with the second group. Then they were tested for play recognition times in a live situation. The group trained with motion pictures had significantly shorter response times. Differences in intelligence, over the limited range used in this study, did not result in differences in response times.

Based on clinical evidence, cryokinetics (alternating cold and exercise) is replacing heat modalities as the preferred therapy for rehabilitation of traumatic musculoskeletal injuries in athletes. Theories have been advanced to explain the clinical successes of cryokinetics, but little scientific data have been collected. Strain gauge plethysmography was used to measure blood flow to the ankle of 12 uninjured male subjects. A repeated measures design was utilized with each subject being tested under six experimental conditions: 1) heat packs, 2) cold packs, 3) control, 4) heat-exercise, 5) cold-exercise, 6) control-exercise. Exercise consisted of 5 three-minute bouts (3.5 mph) interspersed with heat, cold, or control throughout a 45-minute period. Non-exercise, heat and cold were administered for 25 minutes each, followed by 20 minutes without treatment. Instantaneous blood flow was measured regularly during non-exercise periods, estimated during exercise, and total flow was computed by integrating over the 45 minute treatment-post treatment period. Total flow (ml flow/100 ml tissue/min) was greater/p. less than .0002) during cold-exercise than during heat treatments. Contrary to some theories, there was neither cold-induced vasodilatation during, nor a reflex vasodilatation following, the 25-minute cold application. These data suggest that during cryokinetics, exercise causes the increased blood flow, and that cold applications function only to allow active motion in a painful joint.

Appropriate tests can be used to accurately estimate: an individual's potential for success in long distance running; his current level of conditioning; his appropriate training and racing paces; and his ideal bodyweight. The proposed tests include the study of VO2max, running efficiency, maximal steady-state, and body composition. Based on a review of the literature it was determined that VO2max, running efficiency, and body composition provide the information about long distance running potential, including specific paces for various events. Maximal steady-state running pace (pace that elicits 2 mmol/L lactate) identifies appropriate running paces for various events. Relative maximal steady-state oxygen consumption (% VO2max) identifies the current level of conditioning. A comparison of maximal steady-state, running efficiency, and body composition by assessing current status with optimums, provide guidelines for appropriate changes.

Criteria for the identification of maximal steady state as related to state of conditioning were evaluated. 13 volunteers walked and/or ran during a series of 15 min tests on a treadmill. The speeds ranged from mild to exhaustive. Heart rate was monitored continuously; $$\dot V_{O_2 } $$ was determined from 6 min to 9 min; and venous blood was obtained at 10 min and 15 min for lactate analyses. Max $$\dot V_{O_2 } $$ was established for each subject. Subjects were classified on level of conditioning according to the quantity and quality of their activity record for the previous 6 months. The 10 min heart rate associated with a blood lactate level of 2.2 mM/L (MSSHR) was the best predictor of conditioning. The relative $$\dot V_{O_2 } $$ (% of max $$\dot V_{O_2 } $$ ) found with a 10 min blood lactate concentration of 2.2 mM/L (RMSS $$\dot V_{O_2 } $$ ) was almost as accurate as MSSHR in predicting state of conditioning. Changes in blood lactate levels between 10 min and 15 min were not significantly related to conditioning.

Reticulocyte count comparisons were made on ten trained and ten sedentary college males before and immediately after heavy exercise and following 15 min of recovery. No significant differences occurred within or between groups; in fact, all means were within the normal range. Previous findings were discussed. It was concluded that a physiologically significant increase in reticulocytes does not occur as a result of exercise or training and therefore can not be a mechanism for increased maximal oxygen uptake.

The purpose of this study was to investigate the relationship between running pace for the 5 km, the 10 km, and the 16.09 km (10 mile) distances and the following variables: oxygen uptake and treadmill speed at predetermined lactate accumulation points (2.0 and 4.0 mmol.l-1), oxygen uptake (running economy) at three submaximal standardized treadmill speeds (196, 215, and 241 m.min-1), and maximal oxygen uptake. Thirteen moderately to highly conditioned (VO2max = 59.7 +/- 5.3 ml.kg-1.min-1; VO2 at 2.0 mmol.l-1 of plasma lactate = 46.6 +/- 4.1 ml.kg-1.min-1) female runners between the ages of 18 and 33 yr volunteered to participate. All subjects performed the laboratory tests and the 5 km, 10 km, and 16.09 km competitive time trials on an outdoor 5 km course. The correlation coefficients (r) between each race pace and maximal oxygen uptake (VO2max), speed (s) at 2.0 mmol.l-1 plasma lactate accumulation (PLA2s), and speed at 4.0 mmol.l-1 plasma lactate accumulation (PLA4s) ranged between 0.84 and 0.94. The oxygen costs of running at each of the three submaximal paces were correlated moderately with each race pace (r = -0.40 to -0.63). Hierarchal stepwise multiple regression analyses produced equations with two independent variables which explained 94 to 97% of the variability in race performance.