نشریه سوخت و ساز و فعالیت ورزشی
سال دوم شماره 1 (بهار و تابستان 1391)

Physical exercise acts as a mechanical stressor that can elicit biochemical alterations. Thus, muscular effort is able to modify blood concentrations of some cellular enzymes. The purpose of this study was to investigate the effects of one progressive session exercise in day during one week on some enzymes muscle damage such as creatine phospho Kinase (CPK), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) in active girls. thirteen girls students of physical education with mean (Vo2max 41.07±5.11 ml/kg/min) was selected and randomly divided to experimental group (one session of exercise in day, on a treadmill at a rate of 6-8 km/h for 3 min with 1min of active rest between sets until exhaustion, n=7) and control group (n=6). Venous blood samples were obtained for analysis before of exercise (base line) and 1, 4, 7 days during of exercise period, as well as after the 24 hours last progressive session exercise. Data of study were analyzed by repeated measure ANOVA and independent t test. The significant level was set at P≤0.05. The result of this study indicated that AST, LDH and CPK were significantly higher after 1, 4 and 7 days exercise than the resting level (P≤0.05), but after 24 h of end period, this Diff were significantly lower than at the exercise day (P≤0.05). These results suggested that acute exposure to progressive session exercise without adequate recovery can lead to reduced performance and a more dramatically increase in muscle damage enzymes.

The aim of this study was to determin the effect of short-term Coenzyme Q10 supplementation on plasma lactate and serum total creatine kinase (CK) in healthy collegiate men after an aerobic exercise.

Eighteen healthy untrained men (age 24±3 years, body fat 12±2%, and VO2max 39±3 ml/kg/min) in a randomized and double-blind design were allocated in two equal groups: supplement group (n=9, Coenzyme Q10: 2.5 mg/kg/day) and placebo group (n=9, Dextrose: 2.5 mg/kg/day). After supplementation period, all subjects were participated in aerobic exercise protocol with 75% VO2max on the treadmill for 30 minutes. Blood samples obtained before the Q10 supplementation along with immediately before and after the exercise protocol, respectively. Plasma lactate and serum total creatine kinase were determined by automatic analyzers. Data were analyzed by repeated measure ANOVA, Bonferroni and independent t test at P≤0.05.

The results show that short-term Coenzyme Q10 supplementation has no significant effect on basal parameters. However, plasma lactate and serum total CK were significantly increased (P<0.05) after the aerobic exercise. Nevertheless, the change range of lactate, CK after exercise in supplement group was less than in placebo group (P<0.05).

Based on the results, it can be concluded that short-term (14 days) Coenzyme Q10 supplementation can reduce aerobic exercise-induced lactate and creatine kinase elevations (Fatigue and cellular damage indices) in untrained males.

Rapid weight loss (RWL) methods may be cause to reduce physiological capabilities during training or competition periods. In this study, the effect of traditional methods of RWL on anaerobic performance indexes and body composition variables in young wrestlers Thirty-two free style Wrestler males with 19 to 21 years old, body weight 69.28±0.45 kg, and body mass index 23.2±3.6 kg/m2, in two category of weight (60 and 66 kg) were voluntarily participated in this study.First the subject measured reduced body weight by 5±0.1 kg in conventional method and performed, RAST test. After 6 hours with consuming fluid and diet, body composition variable and anaerobic power indexes were measured. According to weight loss recommendations of International Community, two groups of 3% and 5% weight loss were separated and related of parameters were compared. Anthropometric variables and absolute and relative anaerobic powers were changed significant in two groups after 6 hours recovery pursuant to weight reduction (P<0.05). It seems young wrestlers without consideration of international recommendations, reduce 3 to 6 percent of body weight by RWL, 3 to 4 days before the competition. The method of RWL may disturb wrestlers performance.

The aim of this research was to studying the eating disorders in athletic and non-athletic girls with different body compositions. In this research, eating disorders of 570 female athletes (including 277 athletes and 293 non-athletes) were examined with EAT-26 questionnaire. For statistical analysis the U man-Whitney, kruskal-wallis and one way ANOVA tests were used, also Cronbach’s alpha was used for determining interclass consistent reliability of questionnaires. results revealed that athletic female with different body composition haven’t different eating disorder, whereas there are significant differences in eating disorder of overweight non-athletic girls (P<0/01). it’s concluded that there are significant differences between athletes and non- athletes in eating disorders prevalence that this disorders was higher in athletic group.

The purpose of this study was to compare the effects of 1-set and 3-set resistance training on muscular strength of upper-body and lower-body in untrained men. For this reason, 18 untrained college students of Guilan University participate in this study as subject. Subjects were randomly assigned to either the 1-set group (n=9), or the 3-set group (n=9). Subjects trained 3 days per week for 8 weeks. Training intensity was the same for both groups (8RM). At the beginning and the end of the study muscular strength was measured using one repetition maximum test (1RM) in two upper-body exercises (chest press and biceps curl) and two lower-body exercises (leg extension and leg curl). Data was analyzed using paired t-test for within group’s comparison, and unpaired t-test for between-groups comparison. After 8 weeks, muscular strength significantly increased in all of upper-body and lower-body exercises in both groups (P<0.05). The increase in muscular strength in the lower-body exercises was significantly higher in the 3-set group than 1-set group (P<0.05); while no significant difference observed between groups in upper-body exercises. The results demonstrate that 3-set resistance training is superior to 1-set resistance training with regard to strength gains in the lower-body muscles; while no difference exists between 1- and 3-set training with regard to strength gains in upper-body muscles in untrained men.

The aim of this study was to investigate the anthropometric and physiological profiles of senior elite volleyball players according to their playing position. Thirty six national volleyball players (age: 245±45 years) participated in this study. Players were classified to 5 groups according to playing position: setters (n=7), liberos (n=6), middle blockers (n=8), receiver attackers (n=9) and back court attackers (n=6). Physiological variables consists of aerobic fitness (shuttle run test), anaerobic fitness (15s ergojump test), flexibility (sit and reach test), speed (40 yard running), agility (4 9 m test), explosive power (vertical jump) and anthropometric variables consists of weight, height and body fat percent (5 sites skinfold) of participants were measured. Also, their somatotype characteristics were calculated. Liberos were the thinner and shorter than other players (p<005), they also had more agility (p<005). Middle blockers and receive attackers were more ectomorph and mesomorph than other player, respectively (p<005). Setters and liberos had poorer vertical jump performance than other groups (p<005). In addition, Setters and liberos had more flexibility than others (p<005). There were no other significant differences in physiological and anthropometric variables across playing positions. These results suggest that anthropometric and physiological differences exist among volleyball player who play in different position. These differences fit with their different workload in a game. From a practical perspective, sport scientists and coaches should take the physiological and anthropometric characteristics of volleyball players into account when designing individualized position-specific training programs and talent identification.

The aim of this study was comparison between of two resistance training protocols, double pyramid and flat pyramid loading pattern, on physical fitness and body composition in young soccer players. Therefore, 39 young soccer players from Syrian super league were divided randomly into three; control (age: 17.76±0.6 years, weight: 71.9±4 kg, height: 176.2±5 cm and VO2max: 40.7±1.4 ml/kg/min), double pyramid (age 17.46±0.63 years, weight: 71.9±6 kg, height: 176.1±6.7 cm and VO2max 41.2±2) and flat pyramid (age: 18.16±0.83 years, weight: 73.8±7.3 kg, height176.1±5.8 cm and VO2max: 42.3±3.6 ml/kg/min) resistance training groups. The training groups participated 3 times/wk for 8 weeks in resistance training sessions in addition to daily common soccer training sessions. The control group participated only in daily common training sessions. Muscle strength was improved significantly in both double pyramid and flat pyramid loading groups after eight weeks of training (P<0.05) and there were significant differences between these two groups and control group (P<0.05). Both strength training protocols induced no significant differences in BMI and body fat percentage. It can be concluded that double pyramid and flat pyramid loading has no advantage to each other which challenges existing theories in this area. Therefore, more comprehensive works certainly remains to be done because poor body of similar evidence is available.