This investigation examined age related differences in the muscular power of the arms in high school wrestlers. Seventy-five volunteers (M age ±SD = 16.3 ±1.2 yrs) were stratified into four age groups (≤15.00; 15.01−16.00; 16.01−17.00, and ≥17.01 yrs) corresponding approximately to the freshman through senior years of high school. Mean power (MP) and peak power (PP) were measured using an arm crank Wingate Anaerobic Test, and body composition was assessed via underwater weighing. The results indicated significant (p<0.05) group differences for absolute MP and PP as well as for relative MP and PP (covaried for body weight). No significant differences were found when MP and PP were adjusted for fat-free weight (FFW). The results suggested that the age related increases in muscular power of the arms were a function of increases in FFW across age.
Sharon A. Evans, Joan M. Eckerson, Terry J. Housh and Glen O. Johnson
Alan Nevill, Georgia Tsiotra, Panagiotis Tsimeas and Yiannis Koutedakis
We adopted allometric models to identify the most appropriate body size/shape characteristics associated with physical performance activities of Greek school children. Children underwent assessments for aerobic and anaerobic fitness, flexibility and hand-grip strength. Results suggest that the inverse Ponderal index and not BMI is the most appropriate body-shape indicator associated with running and jumping activities. Height was negatively associated with flexibility, but both height and weight were positively associated with hand-grip strength. In conclusion, allometric models provide a valuable insight into the most appropriate body size and shape characteristics associated with children’s physical performances and at the same time ensure valid inference when investigating group/population differences (e.g., between gender and maturation status).
Amândio M.C. Santos, Joanne R. Welsman, Mark B.A. De Ste Croix and Neil Armstrong
Age- and sex-related differences in optimal peak power (PPopt) and associated measures determined using a force-velocity (F-V) cycling test were examined in pre teenage, teenage and adult males and females. Absolute PPopt increased significantly with age in both males and females. With body mass controlled for using allometric scaling significant age related increases remained, an effect masked in the females when PPopt was expressed as W • kg−1. Sex differences in PPopt were minimal in the preteens but males demonstrated higher PPopt than females in both teenage and adult groups. These patterns of change with age and sex broadly reflect those obtained for Wingate Anaerobic Test determined PP but the use of a single non-optimized braking force underestimates the magnitude of any differences observed.
Thomas W. Rowland and Tasha A. Rimany
This study compared aerobic, cardiac, and ventilatory changes in 11 premenarcheal girls ages 9–13 years with those of 13 women ages 20–31 during 40 min of steady-load cycling at an intensity of 63% VO2max. Forty-five percent of the girls were cycling above their ventilatory anaerobic threshold, compared to 77% of the women. Between 10 and 40 min of exercise, mean VO2 increased 8.6% (SD = 3.8) and 8.3% (SD = 6.3) in the girls and women, respectively (p > .05), with no significant differences in rise in body temperature. Pattern and magnitude of ventilatory drift (increased VE and respiratory rate with fall in tidal volume) were similar in the two groups. Likewise, the rise in cardiac output and heart rate (with no change in stroke volume) was not significantly different in the two groups. These findings indicate that physiological responses to prolonged aerobic exercise are both quantitatively and qualitatively similar in girls and young women.
Kari L. Keskinen and Paavo V. Komi
The purpose of this study was to examine the differences in the relationships among the stroking characteristics between different phases of swimming exercises, and to determine whether these relationships would change in relation to enhanced swimming intensity. The experimental design consisted of the measurement of mean velocity (V), stroke rate (SR), stroke length (SL), and duration of different phases of a stroke cycle for each pool length in five to six 400-m swims and two 100-m swims. The results showed that the basic relationships among the stroke parameters during the test exercises were almost similar to those observed in competition. However, the relationships changed with enhanced swimming intensity. It is suggested that the degree of anaerobic lactacid metabolism may determine the characteristics of stroking while swimming. The reduction of SL above the lactate threshold would be connected to the accumulation of blood lactate, whereas SR would primarily be determined by the ability to maintain adequate neural activation.
Abdou Temfemo, Thierry Lelard, Christopher Carling, Samuel Honoré Mandengue, Mehdi Chlif and Said Ahmaidi
This study investigated the feasibility and reliability of a 12 × 25-m repeated sprint test with sprints starting every 25-s in children aged 6–8 years (36 boys, 41 girls). In all subjects, total sprint time (TST) demonstrated high test-retest reliability (ICC: r = .98; CV: 0.7% (95% CI: 0.6–0.9)). While sprint time varied over the 12 sprints in all subjects (p < .001) with a significant increase in time for the third effort onwards compared with the first sprint (p < .001), there was no difference in performance between genders. In all subjects, TST decreased with age (p < .001) and was accompanied by an increase in estimated anaerobic power (p < .001) but also in sprint time decrement percentage (p < .001). Gender did not effect these changes. The present study demonstrates the practicability and reliability of a repeated sprint test with respect to age and gender in young children.
Amanda J. Griffin, Viswanath B. Unnithan and Peter Ridges
The purpose of this study was to assess the effects of a weekend of swimming competition on various physiological parameters in a group of elite female swimmers. Eight female swimmers (age, 16.6 ± 0.5 years) participated in this study. Resting blood lactate (Bla) and heart rate (HR) were taken at the beginning of each testing session. Testing involved a discontinuous incremental peak VO2 treadmill test during which on-line, measures of VO2 were obtained. HR and Bla measurements were taken at the end of each exercise increment. A 30-s leg Wingate test (WAnT) was used to measure anaerobic power. Paired t-tests were carried out on all data. Resting HR was significantly higher and submaximal and maximal HR were significantly lower comparing pre- and postcompetition (p < .005). Resting Bla and submaximal VO2 were significantly higher postcompetition (p < .005). The results suggest that swimming competition causes a number of the recognized symptoms related to excitatory (acute) overtraining
Lothar Rokitzki, Enno Logemann, Georg Huber, Elfriede Keck and Josef Keul
This study was undertaken to evaluate the effects of 5 months of α-tocopherol supplementation on physical performance during aerobic exercise training in 30 top-class cyclists. Antioxidative effects of supplementation were also studied. Plasma α-tocopherol concentration increased significantly in the vitamin E-supplemented group, whereas the placebo group showed a trend toward decrease. Physical performance did not improve in the α-tocopherol-supplemented group compared to the placebo group. Heart rates were also not significantly different. Lactate concentrations at the aerobic threshold and the anaerobic threshold were identical. Thus, there was no performance improvement in the α-tocopherol-supplemented group. However there was a significant reduction in CK in serum of the E-supplemented group. A trend toward decrease in GOT, GPT, and LDH was observed with α-tocopherol supplementation. Moreover, significantly reduced malondialdehyde serum levels were measured in the E-supplemented group. The findings indicate a protective effect of α-tocopherol supplementation against oxidative stress induced by strenuous exercise.
Victoria L. Goosey-Tolfrey
The purpose of this study was to examine the physiological changes in elite wheelchair basketball players leading up to the 2000 Paralympics. Twelve male players attended regular physiological assessments on six occasions; averaged data of two sessions for each year were used. Physiological measures included body mass, skinfold measurements, peak oxygen uptake and peak power obtained during maximal sprinting. VO2peak significantly increased from 2.65 to 2.83 L·min-1 prior to the Paralympics. Training had little influence on the anthropometric measurements or maximal sprinting data. In conclusion, the GB wheelchair basketball players appeared to have high levels of aerobic and anaerobic fitness. The longitudinal physiological profiles leading to the 2000 Paralympics suggest that players improved their aerobic base while maintaining other fitness prerequisites.
James J. Hoffmann Jr, Jacob P. Reed, Keith Leiting, Chieh-Ying Chiang and Michael H. Stone
Due to the broad spectrum of physical characteristics necessary for success in field sports, numerous training modalities have been used develop physical preparedness. Sports like rugby, basketball, lacrosse, and others require athletes to be not only strong and powerful but also aerobically fit and able to recover from high-intensity intermittent exercise. This provides coaches and sport scientists with a complex range of variables to consider when developing training programs. This can often lead to confusion and the misuse of training modalities, particularly in the development of aerobic and anaerobic conditioning. This review outlines the benefits and general adaptations to 3 commonly used and effective conditioning methods: high-intensity interval training, repeated-sprint training, and small-sided games. The goals and outcomes of these training methods are discussed, and practical implementations strategies for coaches and sport scientists are provided.