Anthropometric indices and physical fitness in university undergraduates with different physical activity.

Physical activity and fitness have important health promoting effects with respect to arterosclerosis and coronary heart disease in particular. An intervention study of physical status and physical activity in university undergraduates (University of Tartu) has been carried out. The physically inactive (Group I) consisted of 310 undergraduates (235 females and 75 males) of the Faculty of Medicine. The physically active (Group II) was recruited from among undergraduates (22 females and 23 males) of the Faculty of Exercise and Sport Sciences, who participated in training sessions regularly, 3 to 5 times per week. Anthropometric body measurements, arm force, vital capacity and exercise test on the bicycle ergometer (PWC170) were performed. There were no statistically significant differences between the mean values of anthropometric indices in case of physically inactive and physically active female subjects. In the group of physically active male undergraduates, weight and shoulder width were larger than in students with physically sedentary life style (p < 0.05). Most of the female and male students had normal BMI. There were statistically significant differences in the mean values of vital capacity, arm force and aerobic working capacity between the study groups, while physically active students had higher physical capacity (p < 0.001). Mean anthropometric indices demonstrated a statistically significant increase in both female and male university undergraduates after the interval of 30 years. Normal BMI and anthropometric indices do not serve a as guarantee of physical fitness for university undergraduates who are involved in sedentary life style. Regular physical activity has a strong positive impact on physical fitness, particularly on aerobic capacity which is the most important health promoting component of physical fitness with respect to coronary heart disease.     

Changes in skill and physical fitness following training in talent-identified volleyball players

This study investigated the effect of a skill-based training program on measurements of skill and physical fitness in talent-identified volleyball players. Twenty-six talented junior volleyball players (mean +/- SE age, 15.5 +/- 0.2 years) participated in an 8-week skill-based training program that included 3 skill-based court sessions per week. Skills sessions were designed to develop passing, setting, serving, spiking, and blocking technique and accuracy as well as game tactics and positioning skills. Coaches used a combination of technical and instructional coaching, coupled with skill-based games to facilitate learning. Subjects performed measurements of skill (passing, setting, serving, and spiking technique and accuracy), standard anthropometry (height, standing-reach height, body mass, and sum of 7 skinfolds), lower-body muscular power (vertical jump, spike jump), upper-body muscular power (overhead medicine-ball throw), speed (5- and 10-m sprint), agility (T-test), and maximal aerobic power (multistage fitness test) before and after training. Training induced significant (p < 0.05) improvements in spiking, setting, and passing accuracy and spiking and passing technique. Compared with pretraining, there were significant (p < 0.05) improvements in 5- and 10-m speed and agility. There were no significant differences between pretraining and posttraining for body mass, skinfold thickness, lower-body muscular power, upper-body muscular power, and maximal aerobic power. These findings demonstrate that skill-based volleyball training improves spiking, setting, and passing accuracy and spiking and passing technique, but has little effect on the physiological and anthropometric characteristics of players.     

Effects of a short-term interval training program on physical fitness in prepubertal children

The aim of this study was to analyze the effects of a 7-week interval-training program on different aspects of physical fitness in children who were 8-11 years old. Forty-six boys and 54 girls (9.7 +/- 0.8 years) were divided into an experimental group and a control group. The 2 groups performed selected tests from the European physical fitness test battery before and after training. Training consisted of 2 specific 30-minute sessions per week of short high-intensity, intermittent-running aerobic exercises at velocities ranging from 100-130% of maximal aerobic speed. After training, the experimental group demonstrated a significant improvement in the standing broad jump (9.6%, p < 0.001, F = 12.9) and 20-meter shuttle run (5.4%, p < 0.001, F = 14.4), whereas for the control group, no significant changes were observed. It was concluded that a high-intensity, intermittent-running program improved children's aerobic performance and explosive strength.     

Plyometric training effects on physical fitness and muscle damage in high school baseball players

[Purpose]The objective of this study was to investigate the effects of plyometric training on physical fitness and muscle damage in high school baseball players.[Methods]The participants in the study included 21 high school baseball players who are healthy and well-training. The participants were randomly allocated to the plyometric training (n=11) and control (n=10) groups. The plyometric training was applied 3 times a week for a total of 8 weeks and the control group took part in only regular baseball skills training without plyometric training. For physical fitness, measures included maximal strength (left and right hand-grip strength), muscle endurance (sit-up), agility (side-step), power (standing long jump), and balance (left and right Rhomberg test). For muscle damage, creatine kinase (CK) and lactate dehydrogenase (LDH) levels were measured.[Results]The results showed a significant interaction effect between time and groups in left hand-grip strength (P = 0.022), side-step (P = 0.004), and standing long jump (P < 0.001) after the 8-week plyometric training, with greater improvement in the plyometric training group than the control group. On the other hand, there was no significant interaction effect between time and groups in right hand-grip strength, situp, left and right Rhomberg test, CK level, and LDH level (P > 0.05).[Conclusion]In conclusion, 8-week plyometric training had a positive effect on improving physical fitness, such as maximal strength, agility, and power, in high school baseball players without causing additional muscle damage.     

Regional body composition changes in women after 6 months of periodized physical training.

Data are lacking regarding regional morphological changes among women after prolonged physical training. This study employed dual-energy X-ray absorptiometry to assess changes in whole body and regional (i.e., trunk, legs, arms) fat mass, lean mass, and bone mineral content body composition adaptations in 31 healthy women pre-, mid-, and post-6 mo of periodized physical training. These results were compared with those of 1) a control group of women who had not undergone the training program and were assessed pre- and post-6 mo and 2) a group of 18 men that was tested only once. Additionally, magnetic resonance imaging was used to assess changes in muscle morphology of the thigh in a subset of 11 members of the training group. Physical training consisted of a combination of aerobic and resistance exercise in which the subjects engaged for 5 days/wk for 24 wk. Overall, the training group experienced a 2.2% decrease, a 10% decrease, and a 2.2% increase for body mass, fat mass, and soft tissue lean mass, respectively. No changes in bone mineral content were detected. The women had less of their soft tissue lean mass distributed in their arms than did the men, both before and after the women were trained. Novel to this study were the striking differences in the responses in the tissue composition of the arms (31% loss in fat mass but no change in lean mass) compared with the legs (5.5% gain in lean mass but no change in fat mass). There was a 12% fat loss in the trunk with no change in soft tissue lean mass. Dual-energy X-ray absorptiometry and magnetic resonance imaging fat mass measurements showed good agreement (r = 0. 72-0.92); their lean mass measurements were similar as well, showing approximately 5.5% increases in leg lean tissue. These findings show the importance of considering regional body composition changes, rather than whole body changes alone when assessing the effects of a periodized physical training program.     

The effect of a four-month physical fitness program on a young and an old group matched for physical fitness.

A young (X = 36.8 years) and an old (X = 52.9 years) group (n = 12) matched for physical fitness performed a graded exercise test at the beginning and after a 4-month physical fitness program consisting of calisthenics, jogging, and recreational activities. The purpose of the study was to determine if there were any differences in response to physical training in the two age groups of similar fitness. Sixteen physiological and four biochemical variables were measured. There was no significant difference in VO2 max between the young and old groups. Also, there were no significant differences between groups for serum total lipids, cholesterol, triglycerides, or glucose levels. The effects of the training program were similar for both the young and old groups.     

Thermoregulatory changes in the cold induced by physical training in humans

It has previously been demonstrated that metabolic heat production (M˙) during cold exposure at rest was related to maximal oxygen uptake (O_2max). Consequently, an increase in O_2max could allow an increase M˙ in the cold. The aim of the present study was therefore to test this hypothesis. Eight male volunteers undertook interval training (periods of 25% V˙O_2max of 30-s duration and 110% V˙O_2max of 60-s duration until exhaustion, five times a week over 8 weeks) to increase V˙O_2max. Both before and after this physical training, they were subjected to a 10^∘, 5^∘ and 1^∘C 2-h cold air test in a climatic chamber. During the cold exposure, rectal temperature (T _re), tympanic temperature (T _ty), mean skin temperature () and M˙ were measured as well as the time to onset of shivering (t) and body temperatures () at t. The results showed that physical training involved an increase in O_2max (14%–15%, P < 0.05). During the cold exposure, T _re was higher after training both at 10^∘,5^∘ and 1^∘C (P < 0.05) whereas were not significantly changed. However, an increase in the sensitivity of the thermoregulatory system was attested by a decreased t at higher These slight physiological changes found after training were not related to the increases in V˙O_2max. In conclusion, this study demonstrated that interval training induced slight thermoregulatory changes unrelated to changes in V˙O_2max and it suggested that M˙ during cold exposure could be related mainly to the level of V˙O_2max observed before training, since increases in V˙O_2max did not modify M˙. Accepted: 8 April 1998