Journal of Sport Biosciences
Year:2010 | Volume:- | Issue:6|Papers Count:11

The purpose of the present study was to determine the effect of four weeks of detraining after 12 weeks of continuous and intermittent aerobic training on high sensitive c-reactive protein (HS-CRP) in rats (325.6±4.93 grams and 21 months old and their fertility period expired 3 months ago). For this purpose, 80 female wistar rats with strain 14848 were prepared and divided into three groups: continuous, intermittent aerobic and control and ten subgroups (8 rats were assigned to each subgroup). The training protocol was performed for 12 weeks, 5 days a week with defined speed and duration. Then, the detaining protocol was performed for 4 weeks. The blood samples in the baseline were gathered after 12 to 14 hours of fasting in four phases. The HS-CRP was measured with immunoturbidimetric assay. Also, LDL-C and HDL-C were measured with enzymatic method. Data were analyzed via analysis of variance (ANOVA) and the repeated measure tests and post hoc test of Scheffe. The results showed that HSCRP levels decreased insignificantly in the first six weeks and decreased significantly after 12 weeks. The main results showed that after 4 weeks of detraining, HS-CRP level in continuous and intermittent aerobic groups increased insignificantly and significantly in control group. ANOVA and Scheffe tests showed that HS-CRP difference after 6 and 12 weeks of training and 4 weeks of detraining was not significant only between the continuous and intermittent aerobic groups. It can be stated that continuous and intermittent aerobic training inhibits the inflammatory response and the training type did not affect the levels of HS-CRP during 4 weeks of detraining.

In aim of this research was to investigate the effect of a decrease in the number of practice sessions and an increase in exercise intensity on aerobic and anaerobic power, body fat percentage, and body mass index.80 subjects (average age: 20.2±1.53 years and height: 160.18±5.43cm) were divided into 4 groups (3 experimental groups and one control group). The experimental groups exercised with certain intensity, one, two and three sessions respectively per week for 8 weeks. The exercise consisted of walking and running with certain speeds for each experimental group: three-session group exercised with low intensity (60%-70% maximal heart rate), the two-session group exercised with moderate intensity (70%-80% maximal heart rate) and the one-session group exercised with high intensity (80%-90% maximal heart rate). The findings showed that in factors such as aerobic power, body fat percentage and body mass index, the more the number of sessions and the less the intensity, the better the results for body fat percentage and aerobic power, but the more the intensity and the less the number of the sessions, the better the results for anaerobic power.

The aim of the present study was to evaluate the effect of daily steps on blood lipid profile of middle-aged men. Daily steps were measured in healthy men (n=27) by a portable electronic pedometer. Subjects were voluntarily selected as an active group (AG=12) and sedentary group (SG=15). In addition, total cholesterol (TC), triglyceride (TG), LDL-C and HDL-C were measured. The average of daily steps in the AG (12632±3957 steps/day) was significantly higher than the SG (5347±1631 step/day) (P<0.001). TG and TC concentrations in the AG were significantly lower than SG (P<0.05). TC/HDL-C and LDL-C/HDL-C ratios in AG were significantly lower than SG (P<0.05) whereas HDL-C and LDL-C concentrations were not significantly different in the two groups (P>0.05). It seems that the middle-aged sedentary subjects can improve their cardiovascular system by physical activity of at least 12, 500 steps/day in their morning exercise programs as a threshold of anti-risk factors.

The aim of this study was to examine physiological load imposed on Iranian elite soccer referees during actual match play in the 2007-2008 season. Ten male elite soccer referees (Age: 36.23±2.24 years, height: 180.1±4.48 cm, body mass: 78.18±8.4 kg, fat mass: 19.38±3.3 percent BMI: 23.98±1.53 kg.m-2) participated in the study. Heart rate data were collected during match using the Suunto t6 device during 2 stages with 10 weeks of interval. Paired-sample t-test and repeated measure analysis were used to compare the data of first half and second half and heart rate variations in each half respectively (P<0.05). Average total distance covered was 7872 m (range 6720-9910 m) with mean heart rate 158.63 beats/min (range 145-167) (86 % of maximal heart rate) and no significant differences were observed between halves (p>0.05). Referees, on average, covered 9% of the whole match time at heart rate<140, 72% between 140-170 and 19% of the total time at heart rate>170 and no significant differences were observed between two halves. Also, no significant variations were observed in mean heart rate from first to the last 15 min in each half. In conclusion, these results provided important data to aid the development of training programs according to physiological load imposed on elite soccer referees during actual match play.

The purpose of this study was to investigate the effects of short-term creatine monohydrate (CR) and folic acid (FA) supplementation on homocysteine (Hcy) levels in young active males. Eighteen young male soccer players (21.11±2.02 years, VO2max 56.51±2.31, Hcy 13.45±0.59) volunteered to participate in this study. They were randomly divided into creatine monohydrate (n=6), folic acid (n=6) and placebo (n=6) groups. Blood samples were gathered before (at least 12 hours of fasting) and immediately after the exhaustive exercise. Each subject of FA group received 14 folic acid capsules (800mg/d) for 9 days and 0.3 g/kg/wt/d placebo+folic acid capsules for 5 days. CR group received placebo for 9 days and then 0.3 g/kg/wt/d creatine monohydrate+placebo for 5 days. Again after 2 weeks of supplementation, in at least 12h fasting, blood samples were gathered before, and immediately after the exhaustive exercise. Results showed that Hcy significantly decreased after supplementation in creatine monohydrate group, but there was no significant difference in Hcy between the two groups. Hcy significantly decreased immediately after the exercise in creatine group when compared to the pretest. There was a significant difference between creatine and acid folic groups as well as between creatine and placebo (p=0.001 and p=0.002 respectively), but there was no significant difference between acid folic and placebo groups (p=0.714). Overall, the findings showed that short-term creatine monohydrate supplementation can significantly decrease Hcy levels after the exhaustive exercise, but short-term folic acid supplementation did not significantly affect basic Hcy and immediately after the exhaustive exercise.

The purpose of the present study was to compare some biochemical markers of cancer diseases risk between two groups of active and inactive postmenopausal women. For this purpose, 74 postmenopausal women were required to complete Baecke questionnaire. They were divided into two groups: active (age: 55.89±.38 years, height: 156.93±0.05 cm, weight: 63.18±6.50 kg, body fat percentage: 26.25±6.29, body mass index: 25.79±2.37 kg/m2, VO2max: 34.02±5.08 ml/kg min) and inactive (age: 57±4.80 years, height: 156.95±0.052 cm, weight: 65.9±7.67 kg, body fat percentage: 27.07±6.44, body mass index: 26.69±1.95 kg/m2, VO2max 24.21±2.10 ml/kg/min). Blood samples were gathered in a fasting state. Independent T test was used to analyze data. The results of this study showed that IGF-1 level was significantly higher in active postmenopausal women than inactive postmenopausal women. There were not significant difference between active and inactive postmenopausal women in IGFBP-3, IGF -1/ IGFBP-3, insulin, glucose and insulin resistance index. In conclusion, chronic physical activity could cause optimal levels for biochemical markers of cancer diseases risk.

The present study attempted to compare the structural and functional changes of left heart ventricle in female basketball players of Khuzestan superior league (aged between 18 and 29) during regular training and long-term detraining. Out of 30 female players, 15 subjects were assigned randomly to regular training group and 15 subjects to long-term detraining group. The structural and functional variables of left heart ventricle included end-systolic and end-diastolic internal diameter (LVEDS, LVEDD respectively), septum and posterior wall thickness (SWT, PWT respectively), left ventricular mass (LVM), stroke volume (SV), ejection fraction (EF) and rest heart rate (HR). These variables were studied and measured at rest by mono and two dimensional echocardiography and color Doppler technique. In order to analyze the collected data, descriptive statistics and multianalysis of variance (MANOVA) were used (P<0.05). Findings of the study showed that regular training group enjoyed significantly higher structural and functional variables of left heart ventricle (except in the cases of end-systolic and posterior wall thickness) and lower rest heart rate compared with long-term detraining group. Overall results of this study revealed that left heart ventricular structure can positively be affected by basketball regular training.

The full text of this article is the Persian language, please for the view full text, refer to Persian.Please click here to view the full text of this article.