摘要:

Impairment in strength development has been demonstrated with combined strength and endurance training as compared with strength training alone. The purpose of this study was to examine the effects of combining conventional 3 d·wk−1strength and endurance training on the compatibility of improving both &OV0312;O2peakand strength performance simultaneously. Sedentary adult males, randomly assigned to one of three groups (N= 10 each), completed 10 wk of training. A strength-only (S) group performed eight weight-training exercises (4 sets/exercise, 5–7 repetitions/set), an endurance-only (E) group performed continuous cycle exercise (50 min at 70% heart rate reserve), and a combined (C) group performed the same S and E exercise in a single session. S and C groups demonstrated similar increases (P< 0.0167) in 1RM squat (23% and 22%) and bench press (18% for both groups), in maximal isometric knee extension torque (12% and 7%), in maximal vertical jump (6% and 9%), and in fat-free mass (3% and 5%). E training did not induce changes in any of these variables. &OV0312;O2peak(ml·kg−1min−1) increased (P< 0.01) similarity in both E (18%) and C (16%) groups. Results indicate 3 d·wk−1combined training can induce substantial concurrent and compatible increases in &OV0312;O2peakand strength performance.

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

The purpose of this study was to examine the effects of menstrual cycle phase on four selected indices of athletic performance: aerobic capacity, anaerobic capacity, isokinetic strength, and high intensity endurance. Sixteen eumenorrheic women (&OV0312;O2max≥ 50 ml·kg−1·min−1) were tested during the early follicular (F) and midluteal (L) phases of the menstrual cycle. Cycle phases were confirmed by serum estradiol and progesterone assays. No significant differences were observed between F and L tests in weight, percent body fat, sum of skinfolds, hemoglobin concentration, hematocrit, maximum heart rate, maximum minute ventilation, maximum respiratory exchange ratio, anaerobic performance, endurance time to fatigue (at 90% of &OV0312;O2max), or isokinetic strength of knee flexion and extension. Both absolute and relative &OV0312;O2max, however, were slightly lower in L than in F (F = 3.19 ± 0.09·min−1, L = 3.13 ± 0.08·min−1,P= 0.04; and F = 53.7 ± 0.9 ml·kg−1·min−1, L = 52.8 ± 0.8 ml·kg−1·min−1,P= 0.06). These results suggest that the cyclic increases in endogenous female steroid hormones of an ovulatory menstrual cycle may have a slight, deleterious influence on aerobic capacity, with potential implications for individual athletes. Nevertheless, the cycle phase did not impact significantly on the majority of the other performance tests and cardiorespiratory variables measured in this study.

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

The purpose of this study was to develop and cross-validate a generalized equation for predicting &OV0312;O2peakfrom 1-mile run/walk (MRW) time and demographic variables in youth and young adults. Data for 753 males and females 8–25 yr of age were divided into validation (N= 495) and cross-validation (N= 258) samples. The validation sample was used lo develop a multiple regression equation for predicting treadmill &OV0312;O2peak(ml·kg−1min−1) from gender (0 = F, 1 = M), age (yr), body mass index (kg·m−1; BMI) and MRW time (min). The multiple correlation (R) and standard error of estimate (SEE) were: R = 0.71, SEE = 4.8 ml·kg−1·min−1. The accuracy of this equation was confirmed when applied to the cross-validation sample. The regression equation for the total sample was: &OV0312;O2peak= −8.41 (MRW) + 0.34 (MRW)2+ 0.21 (Age × Gender) −0.84 (BMI) + 108.94, R = 0.72, SEE = 4.8 ml·kg−1·min−1. We conclude that the generalized equation provides valid estimates of &OV0312;O2peakin youth and young adults. The equation should be useful for educators, clinicians, and researchers who would like to interpret results of the MRW test in terms of &OV0312;O2peak.

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Simple, valid, and reliable methods of estimating maximal oxygen uptake (&OV0312;O2max) are needed for epidemiologic studies of physical activity, to evaluate fitness for job performance, and to assist in prescription of exercise. Such estimations in women have not received due research attention. Heart rate responses to submaximal cycle ergometry and &OV0312;O2maxduring maximal treadmill and cycle ergometer testing were measured in 37 healthy women aged 19–47 yr (X = 31.7 ± 7.9). The submaximal test was very reliable on retest (r = 0.92), but overestimated measured treadmill &OV0312;O2max(&OV0398; = 2.42 vs 2.23 1·min−1; r = 0.76, SEE = 0.229). The submaximal test also greatly overestimated maximal cycle ergometer &OV0312;O2max(&OV0398; = 2.42 vs 2.06 1·min−1; r = 0.70, SEE = 0.340). Similar 8.5% (treadmill) and 18.5% (cycle ergometer) overestimations by the submaximal test were found for &OV0312;O2maxrelative to body weight. A simple submaximal exercise test is highly reliable as an estimate of &OV0312;O2maxwhen used for women. It also provides a reasonably good estimate of treadmill measured &OV0312;O2max.

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

The purpose of the study was to compare the %&OV0312;O2maxversus %HRmaxregression 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. &OV0312;O[sb]2[/sb] 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 %&OV0312;O2max-%HRmaxregressions. However, weight supported and arm exercise modes appear to have different regressions.

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID