Perceived exertion responses to novel elbow flexor eccentric action in women and men

PURPOSE: The primary aim was to describe perceived exertion responses to different intensities of eccentric exercise in women and men. METHODS: 42 adults (21 men and 21 women, 7 per condition) completed elbow extension exercises with a weight corresponding to 80%, 100%, or 120% of maximal voluntary concentric strength. Total work was equated by manipulating the number of repetitions in the 80% (N = 45), 100% (N = 36), and 120% (N = 30) conditions. RESULTS: A two-way ANOVA showed significant main effects for the intensity and sex factors. Perceived exertion ratings were strongly dependent on exercise intensity, and women reported lower RPEs than men. A separate three-way mixed model ANOVA that included a repetition factor showed that perceived exertion ratings increased similarly across the first 30 repetitions in all exercise conditions. Significant partial correlations were found between mean RPE during the eccentric exercise bout, and the mean intensity of delayed-onset muscle pain measured from 12- to 72-h postexercise after controlling for the relative exercise intensity (r12.3 = 0.28) or the maximum concentric strength of the elbow flexors (r12.3 = 0.33). CONCLUSIONS: 1) for both women and men, there is a positive association between the intensity of eccentric exercise performed with the elbow flexors and RPE; 2) perceived exertion ratings increase significantly then plateau when repeated eccentric muscle actions are performed at constant, submaximal absolute intensities; 3) women rate eccentric exercise performed at the same intensity (relativized to MVC-C) as being less effortful compared with men; and 4) RPE during eccentric exercise can account for a small but significant amount of variability in delayed-onset muscle pain after statistically controlling for differences in strength or relative intensity.     

Intermodal comparison of energy expenditure at exercise intensities corresponding to the perceptual preference range

PURPOSE: This study compared the rate of energy expenditure among six popular exercise machines at intensities corresponding to ratings of perceived exertion (RPE) for fairly light (RPE-11), somewhat hard (RPE-13), and hard (RPE-15) in 9 healthy men and 10 healthy women. METHODS: A maximal exercise test on each exercise machine was used to anchor the Borg 15-point category scale. Subjects performed three submaximal exercise tests at selected RPEs on a treadmill, stair-stepper, cycle ergometer, rowing ergometer, cross-country ski simulator, and rider. The submaximal tests on each exercise device were performed in random order and were 6 min in duration with 15-min rest between trials. Oxygen uptake, heart rate, and blood lactate concentration were measured during the final 2 min of each exercise intensity. RESULTS: Energy expenditure at each RPE was highest on the treadmill and ski simulator in men, and on the treadmill, ski simulator, and rowing ergometer in women. Energy expenditure in men and women at all RPEs was lowest on the rider and cycle ergometer. Energy expenditure at a given RPE was greater in men than women on all exercise machines, but men and women used a similar percentage of their machine specific peak oxygen uptake at each RPE on all machines. Heart rate was generally similar among the machines and between both men and women at each RPE. CONCLUSIONS: Our results indicated that there are large differences in energy expenditure between exercise machines and between men and women at intensities perceived to be fairly light, somewhat hard, and hard. Consequently, subjects can expend more calories at the same RPE during treadmill and ski simulator exercise, for example, than during exercise with other devices. This may have important implications for the health benefits of different exercises and in promoting long term exercise adherence.     

Validation of the Adult OMNI Scale of perceived exertion for walking/running exercise

PURPOSE: Concurrent and construct validity of the OMNI-Walk/Run Scale of Perceived Exertion was examined using young adult women and men (18-36 yr). METHODS: Concurrent validity was established by correlating OMNI-Walk/Run Scale ratings of perceived exertion (RPE-OMNI) with oxygen uptake (VO2), relative maximal oxygen uptake (%VO2(max)), ventilation (VE), respiratory rate (RR), respiratory exchange ratio (RER), and heart rate (HR) to a graded exercise test on a treadmill. Construct validity was established by correlating RPE-OMNI with RPE from the Borg (6-20) Scale (RPE-BORG). Measurements were made every min throughout the test. RESULTS: The range of exercise responses across the incremental walking/running test for the female and male groups were: VO2 = 0.99-3.9 L x min(-1), HR = 98-190 beats x min(-1) and RPE-OMNI = 1.3-9.4. Correlation/regression analyses indicated that RPE-OMNI distributed as a positive linear function for all criterion measures; r = 0.67 to 0.88 (P < 0.05). RPE-OMNI was positively and linearly related to the RPE-BORG; r = 0.96 (P < 0.01) for both the female and male groups. CONCLUSIONS: Concurrent and construct evidence supports use of the OMNI-Walk/Run Scale by adult women and men to estimate RPE during graded exercise test on a treadmill.     

Validation of the adult OMNI scale of perceived exertion for cycle ergometer exercise

PURPOSE: Concurrent and construct validity of the OMNI-Cycle Scale of Perceived Exertion were examined using young adult women and men (18-32 yr). METHODS: Concurrent validity was established by correlating OMNI-Cycle Scale ratings of perceived exertion (RPE) with oxygen consumption (.VO2) and heart rate (HR) responses to a load-incremented cycle ergometer protocol. Construct validity was established by correlating RPE derived from the OMNI-Cycle Scale with RPE from the Borg (6-20) Scale. RPE, .VO2, and HR were measured during each exercise stage. RESULTS: The range of exercise responses across the incremental test for the female and male groups was .VO2 = 0.92-2.74 L.min-1, HR = 107.2-167.2 beats.min-1, and OMNI Scale RPE-Overall, RPE-Legs, and RPE-Chest 1.0-9.1. Correlation/regression analyses indicated that RPE-Overall, RPE-Legs, and RPE-Chest distributed as a positive linear function of both .VO2 and HR (r = 0.81 to 0.95; P < 0.01). Undifferentiated and differentiated RPE-OMNI Scale distributed as a positive linear function of RPE-Borg Scale (r = 0.92 to 0.97; P < 0.01). ANOVA indicated that OMNI-Cycle RPE-Legs was higher (P < 0.01) than RPE-Chest at each exercise stage for both genders. CONCLUSION: Concurrent and construct evidence supports use of the OMNI Scale by adult women and men to estimate RPE during cycle exercise.     

The reproducibility of perceptually regulated exercise responses during short-term cycle ergometry

The purpose of this study was to assess the reproducibility over four trials of perceptually regulated exercise intensity during short-term cycle ergometry. Recent research has suggested that an improvement in the reproducibility (better agreement) of the exercise output would be observed with a repeated practice using regulatory tools such as Borg's 6 - 20 rating of perceived exertion (RPE) scale. Eighteen healthy active volunteers (nine males, mean age (+/- SD) 24.7 +/- 3.4 yr, and nine females 27.6 +/- 5.4 yr) completed four identical intermittent effort production trials on a cycle ergometer over a period of two - three weeks, with all trials being between three and five days apart. After warm-up, the volunteers were asked to produce four x three-minute bouts of exercise at RPE levels: 13, 15, 9, and 17 (in this order). Power output (W), percentage maximum heart rate reserve (%MHRR), and oxygen consumption (VO(2); ml x kg(-1) x min(-1)) were recorded in the final minute of each bout. Analysis revealed that the 95 % limits of agreement (LoA) between repeated trials did not decrease for the objective markers of exercise intensity, remaining wide throughout. In the worst case comparisons the LoA represented changes (expressed as a proportion of the mean of two trials) of up to 58.3 % in power output (T2 vs. T3 at RPE 9), 65.5 % in % MHRR (T1 vs. T2 at RPE 13) and 36.5 % in VO(2) (T3 vs. T4 at RPE 17). These findings question the use of ratings of perceived exertion to regulate exercise effort. That the reproducibility of effort is also not seen to improve with practice raises doubts about the validity of using the RPE scale to provide training intensities for this type of exercise.     

A comparison of physiological responses and rating of perceived exertion in two modes of aerobic exercise in men and women over 50 years of age

OBJECTIVES: To compare the physiological responses and ratings of perceived exertion to aerobic dance and walking sessions completed at a self selected pace. METHODS: Six women and six men with a sample mean (SD) age of 68 (7) years completed aerobic dance and walking sessions in random order. A treadmill test was performed by each subject from which peak oxygen uptake (.VO(2)) and maximum heart rates (HRmax) were determined. During the aerobic dance and walking sessions, heart rate and .VO(2) were measured continuously throughout. Rate of perceived exertion (RPE) was measured every three minutes throughout the session. RESULTS: The sample means (SD) for %peak .VO(2) were 67 (17)% for the aerobic dance sessions and 52 (10)% for the walking sessions, and the %HRmax sample means (SD) were 74 (12)% for the aerobic dance sessions and 60(8)% for walking sessions. The sample mean (SD) RPE for the aerobic dance sessions was 11(2), and for the walking sessions it was 10(2). CONCLUSIONS: %peak .VO(2), %HRmax, and RPE were significantly higher for aerobic dance than for walking. However, both the aerobic dance and walking sessions were of adequate intensity to improve aerobic fitness in most subjects. Further investigation into the relation between RPE and %peak .VO(2) in a field setting over representative exercise time periods would be useful.     

Exercise intensity and perceived exertion in adolescent boys.

The rating of perceived exertion (RPE) was assessed at power outputs (PO) corresponding to 30%, 60% and 90% of predicted maximal oxygen uptake (VO2 max) on a cycle ergometer in 30 adolescent schoolboys (age range 15-17 years). Analysis of correlations (r) for heart rate (HR):PO (r = 0.74 p less than 0.01) and rating of perceived exertion (RPE): HR (r = 0.74 p less than 0.01) were similar to values drawn from adult samples. It was concluded that there is a close relationship between RPE, HR and relative exercise intensity in adolescent schoolboys.     

Perceptual responses and blood lactate concentration: effect of training state

The present study investigated the effect of training state on ratings of perceived exertion obtained at the lactate threshold (LT) and fixed blood lactate concentrations (FBLC) of 2.0, 2.5, and 4.0 mM. Runners (N = 20) and nonrunners (N = 29) completed a progressive horizontal treadmill (TM) running test which allowed identification of the TM velocities associated with the LT and FBLC. Runners attained significantly higher TM velocities, greater VO2, greater VE, greater heart rate, and a lower ventilatory equivalent for oxygen (VE/VO2) at each exercise intensity, with the exceptions of heart rate at 4.0 mM and VE/VO2 at the LT. Compared to nonrunners, runners also attained higher VO2, VE, and heart rate relative to peak values at LT and 2.0, 2.5, and 4.0 mM. Despite these relative and absolute physiological differences, there were no differences between groups in local, central, or overall ratings of perceived exertion (RPE) (Borg scale) at any condition. The data from both groups were combined to give the following means and SD for overall RPE during horizontal running: at the LT-11.0 +/- 2.0, and at FBLC of 2.0 mM-13.7 +/- 2.1, 2.5 mM-14.5 +/- 1.8, and 4.0 mM-16.5 +/- 2.3.     

Effect of exercise modality on ratings of perceived exertion at various lactate concentrations

The effect of exercise modality on the relationship between ratings of perceived exertion (RPE), blood lactate concentration, oxygen uptake (VO2), and heart rate (HR) was examined in 29 untrained male subjects who completed counterbalanced VO2max/lactate threshold (LT) protocols on a cycle ergometer (CE) and treadmill (TM). Heart rate, VO2, and RPE were determined at power outputs corresponding to LT and fixed blood lactate concentrations (FBLC) of 2.0, 2.5, and 4.0 mM and during maximal exercise. A repeated measures ANOVA indicated that, despite significant differences across exercise modality in HR and VO2 at LT, FBLC, and maximal exercise, no significant differences in RPE were found between exercise modalities during leg exercise. Mean (+/- SD) respective values for overall RPE at LT and FBLC of 2.0 mM, 2.5 mM, 4.0 mM, and max were 10.2 (2.2), 13.1 (2.1), 14.1 (2.3), 15.9 (2.3), and 18.8 (1.3) for the CE and 10.8 (1.9), 13.8 (1.8), 14.6 (1.6), 16.2 (2.6), and 18.5 (1.5) for the TM. It was concluded that exercise modality does not affect the perception of exertion at LT, FBLC, or maximal exercise and that a strong relationship exists between RPE and blood lactate concentrations.     

Ratings of perceived exertion in braille: validity and reliability in production mode

OBJECTIVES: (a) To assess the validity and reliability of producing and reproducing a given exercise intensity during cycle ergometry using a braille version of Borg's standard 6-20 rating of perceived exertion (RPE) scale, and (b) to determine whether the exercise responses of blind participants, at a given produced RPE, were similar to those reported in recognised guidelines for sighted subjects. METHODS: Ten healthy registered blind volunteer participants (four women, six men; mean (SD) age 23.2 (9.0) years) performed an initial graded exercise cycle test to determine maximal heart rate (HRMAx) and maximal oxygen uptake (VO2MAX). Three trials of three exercise bouts at RPEs 9, 11, and 13 were then performed in random order on three separate days of the same week, with expired air and heart rate measured continuously. Each exercise bout was followed by 10 minutes of rest. The validity of the scale as a means of producing different exercise intensities was assessed using a two factor (RPE x trial) repeated measures analysis of variance. Intertrial reliability was assessed using intraclass correlation coefficients (ICC) and the bias +/-95% limits of agreement (95%LoA) procedure. RESULTS: Participants reported no difficulty in using the braille RPE scale. When asked to produce exercise intensities equating to RPE 9, 11, and 13, they elicited mean %VO2MAX values of 47%, 53%, and 63% respectively. Analysis of variance showed no significant differences in either %HRMAx or %VO2MAX between trials at each of the three RPEs, but there was a significant difference (p<0.001) in both %HRMAx and %VO2MAX between the three RPE levels. All pairwise comparisons of the three different RPEs were significantly different (p<0.016). The ICC between the second and third trial for %HRMAx was significant (p <0.05) for all three RPEs. Similarly for %VO2MAX, the ICC was significant for RPE 9 and 11 but not 13. The 95%LoA decreased for both %HRMAx and %VO2MAX with each successive trial. CONCLUSIONS: Blind participants were successful in using a braille RPE scale to differentiate exercise intensity on a cycle ergometer. In every trial at RPE 13, all participants achieved %HRMAX and %VO2MAX levels, which fell within the recommendedrange for developing cardiorespiratory fitness. Using %HRMAx as a judge of intertrial reliability, the participants were able to repeat similar exercise intensities after two trials at each of the three RPEs (9, 11,13). The same was true for RPE 9 and 11, when %VO2MAX was used as a judge, but further trials were required to achieve similar reliability at RPE 13. A braille RPE scale can be used by healthy blind people during cycle ergometry, with similar effect to the visual analogue scale recommended for use in healthy sighted people.     

Responses of aerobically fit men and women to uphill/downhill walking and slow jogging

Few studies have thoroughly examined metabolic, cardiovascular, and psychophysiological responses to negative treadmill (TM) exercise. We compared oxygen consumption (VO2), heart rate (HR), and perceived exertion (RPE, 0-10 Borg scale) during incremental TM exercise featuring both downhill and uphill stages. Subjects were aerobically trained males (N = 12, VO2max = 61 ml.kg-1.min-1) and females (N = 12, VO2max = 53 ml.kg-1.min-1). On separate occasions, each subject walked (4.8 kph) or jogged (9.6 kph) for 25 min. Five minutes were spent at each of five grades (-10, -5, 0, 5, 10%, or the reverse). TM speed and percent progressions were randomized. VO2 and HR did not differ in the 4.8 kph condition when TM grade was negative. During 9.6 kph, both VO2 and HR significantly (P less than 0.001) increased with progressive increments, but increases were less when TM grade was negative. RPE did not differ in the 4.8 kph condition except at 10% grade, where responses were significantly (P less than 0.001) higher. In 9.6 kph, RPE responses were significantly (P less than 0.001) greater during positive stages. The only gender effect occurred at 10% in the 9.6 kph condition, where women had greater (P less than 0.01) RPE responses than men. Results suggest that both walking and jogging economies differ between negative and positive TM grades. Gender differences appear negligible when comparing aerobically trained men and women.     

Perceived exertion in fatiguing illness: civilians with chronic fatigue syndrome

PURPOSE: It has been reported that ratings of perceived exertion (RPE) are elevated in chronic fatigue syndrome (CFS). However, methodological limitations have rendered this conclusion suspect. The purpose of the present investigation was to examine RPE during exercise in civilians with CFS by comparing subjects at both absolute exercise stage and relative oxygen consumption reference criteria. METHODS: A sample of 39 civilian females (N = 19 CFS, 34 +/- 7 yr; N = 20 healthy controls, 33 +/- 7 yr) underwent a maximal exercise test on a treadmill. RPE were obtained during the last 15 s of each 3-min stage using Borg's 6-20 scale. RESULTS: There were no significant differences in peak [OV0312]O(2), RER, or RPE. However, controls exercised longer (20.0 +/- 1.1 vs 15.9 +/- 1.1 min, P = 0.01, healthy vs CFS) and had higher peak HR (183 +/- 3 vs 174 +/- 2 bpm, P = 0.03, healthy vs CFS). Civilians with CFS reported higher RPE at stages 3 through 5 compared with controls (F(3,111)= 3.6,P = 0.017). Preexercise fatigue ratings were not a significant predictor of perceived exertion during exercise. There were no group differences (F(1,37)= 1.9, P = 0.17) when RPE were expressed relative to peak [OV0312]O(2). CONCLUSIONS: Our results show that RPE are greater in civilians with CFS when the data are expressed in terms of absolute exercise intensity. However, by examining RPE relative to a common maximum (i.e., peak [OV0312]O(2)) no differences were observed. The findings of the present investigation challenge the notion that RPE are dysregulated in CFS.     

Reliability and validity of measures taken during the Chester step test to predict aerobic power and to prescribe aerobic exercise

OBJECTIVES: To evaluate the reliability and validity of measures taken during the Chester step test (CST) used to predict VO(2)max and prescribe subsequent exercise. METHODS: The CST was performed twice on separate days by 7 males and 6 females aged 22.4 (SD 4.6) years. Heart rate (HR), ratings of perceived exertion (RPE), and oxygen uptake (VO(2)) were measured at each stage of the CST. RESULTS: RPE, HR, and actual VO(2) were the same at each stage for both trials but each of these measures was significantly different between CST stages (p<0.0005). Intertrial bias +/-95% limits of agreement (95% LoA) of HR reached acceptable limits at CST stage IV (-2+/-10 beats/min) and for RPE at stages III (0.2+/-1.4) and IV (0.5+/-1.9). Age estimated HRmax significantly overestimated actual HRmax of 5 beats/min (p = 0.016) and the 95% LoA showed that this error could range from an underestimation of 17 beats/min to an overestimation of 7 beats/min. Estimated versus actual VO(2) at each CST stage during both trials showed errors ranging between 11% and 19%. Trial 1 underestimated actual VO(2)max by 2.8 ml/kg/min (p = 0.006) and trial 2 by 1.6 ml/kg/min (not significant). The intertrial agreement in predicted VO(2)max was relatively narrow with a bias +/-95% LoA of -0.8+/-3.7 ml/kg/min. The RPE and %HRmax (actual) correlation improved with a second trial. At all CST stages in trial 2 RPE:%HRmax coefficients were significant with the highest correlations at CST stages III (r = 0.78) and IV (r = 0.84). CONCLUSION: CST VO(2)max prediction validity is questioned but the CST is reliable on a test-retest basis. VO(2)max prediction error is due more to VO(2) estimation error at each CST stage compared with error in age estimated HRmax. The HR/RPE relation at >50% VO(2)max reliably represents the recommended intensity for developing cardiorespiratory fitness, but only when a practice trial of the CST is first performed.     

Prescribing water-based exercise from treadmill and arm ergometry in cardiac patients.

This study investigated the appropriateness of prescribing upright water-based exercise from treadmill and arm ergometry in uncomplicated, trained patients with cardiovascular disease (CVD) who were accustomed to water-based activities. Ten male patients with established CVD (mean age 59.4 +/- 8.7 yr) underwent maximal treadmill and arm ergometry in randomized counterbalanced order (half of the patients completed the treadmill test first and the other half completed the arm ergometer test first). Electrocardiographic (ECG), rating of perceived exertion (RPE), and oxygen uptake (VO2) measurements were made during both tests. Patients performed upright water-based exercise at 60, 70, and 80% of their maximal treadmill heart rate for 6 min at each intensity in a heated pool with a water temperature of 28-30 degrees C. They also performed an easy tethered swim, defined as performing at a comfortable exercise intensity, eliciting a heart rate of 86% of the treadmill maximum. VO2 and RPE were collected for all water-based exercise. To compare the RPE and VO2 between water-based, treadmill, and arm ergometry exercise, individual regression equations were constructed between heart rate, VO2, and RPE for both treadmill and arm ergometry tests. VO2 and RPE were then compared at the same heart rates between the three exercise modes. At 60% intensity, treadmill exercise exhibited a higher VO2 than water-based and arm ergometry exercise (P less than 0.05) but similar RPE. At 70%, treadmill exercise still yielded higher VO2, but also lower RPE than (P less than 0.05) and arm ergometry exercise (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

The influence of fitness and body weight on preferred exercise intensity

PURPOSE: The purpose of this investigation was to determine the individual and combined effects of aerobic fitness and body weight on physiological responses, perceived exertion, and speed variables during self-selected steady-state treadmill (TM) walking in 60 healthy college-age women. METHODS: The women were placed into one of four categories based on body mass index (BMI) and fitness level, assessed by a graded TM test. Subjects walked continuously on a TM at a self-selected pace for 15 min at a 2.5% grade. The dependent variables were oxygen uptake (VO(2)), HR, percentage of maximal oxygen uptake (VO(2max)), percentage of HRmax (%HRmax), RPE for the overall body, TM belt speed, and total energy expenditure (EE). RESULTS: There were no significant interactions or body weight main effects for any of the dependent variables. However, lower-fitness subjects walked at a TM speed that resulted in a higher (P < 0.0005) VO(2max) (52.4 vs 39.56) than the higher-fitness subjects. CONCLUSION: These findings suggest that fitness, and not body weight, influences preferred exercise intensity as measured by VO(2max) during TM walking in college-age women. The self-selected walking speed did not result in an intensity, as determined by VO(2max), that is consistent with the enhancement of cardiorespiratory fitness for higher-fitness women regardless of body weight.     

Physiological and perceptual responses to cycle and treadmill exercise during pregnancy

We compared physiological and perceptual responses to non-weight bearing (cycle) and weight bearing (treadmill) exercise in 16 sedentary women throughout a normal term pregnancy. Subjects were recruited late in the first trimester (less than 13 wk gestation) and were studied at 4 wk intervals throughout pregnancy and 4 wk postpartum (PP). Exercise consisted of four 5 min protocols; two were performed on the cycle (C1 = 50 W; C2 = 75 W) and two on the treadmill (T1 = 66 m.min-1, 2.5% grade; T2 = 66 m.min-1, 12% grade). Measured variables included oxygen consumption (VO2), heart rate (HR), minute ventilation (VE), and ratings of perceived exertion (RPE, 10-point Borg scale). Absolute VO2 (ml.min-1) during cycle exercise increased (P less than 0.001) by 25 wk gestation, while relative VO2 (ml.kg-1.min-1) during treadmill walking was unchanged through late pregnancy and PP. This suggests that cycle exercise is not a true non-weight bearing exercise within a given group of women throughout gestation. Subjects' VO2max values were estimated at each test interval and found to increase (P less than 0.001) by 25-28 wk gestation. Heart rate and RPE responses to exercise remained constant throughout gestation and decreased (P less than 0.01) PP. Although they did not participate in a regular exercise program, it appears that our subjects experienced a mild aerobic training effect during late pregnancy.     

Leisure-time physical activities and their relationship to cardiorespiratory fitness in healthy men and women 18-95 years old

PURPOSE: We examined leisure-time physical activities (LTPA) and their contribution to peak oxygen consumption (VO2) in healthy men (N = 619) and women (N = 497) aged 18-95 yr (mean 51 +/- 17) who were participants of the Baltimore Longitudinal study of Aging. METHODS: Calculations of LTPA were based on the average self-reported time spent performing 97 activities and converted into MET-min x 24 h(-1). The activities were divided into three levels of LTPA based on absolute intensity. Peak VO2 was determined from a maximal treadmill exercise test. RESULTS: Total LTPA was inversely related to age in both sexes (r = -0.26, P < 0.0001 in men and r = -0.23, P < 0.0001 in women), mediated primarily by less high-intensity activities in older subjects, with only minor differences in moderate- and low-intensity activities across age. Peak VO2 correlated positively with LTPA; the correlations were strongest for high-intensity LTPA (r = 0.33 in men and 0.27 in women, each P < 0.0001), intermediate for moderate-intensity activity (r = 0.12, P < 0.004 in men and r = 0.17, P < 0.0001 in women) and minimal for low-intensity activity (r = 0.08, P = 0.05 in men and r = 0.06, P = 0.20 in women). On univariate analysis, total LTPA accounted for 12.9% of peak VO2 variance for men and 10.6% for women. By multivariate analysis, LTPA independently accounted for 1.6% of the peak VO2 variance in men and 1.8% in women after controlling for age and body mass index. CONCLUSIONS: In healthy adults across a broad age range, LTPA is a relatively minor independent contributor to aerobic capacity.