جستجوی مقالات مرتبط با کلیدواژه "high intensity interval exercise" در نشریات گروه "تربیت بدنی"

To investigate the effect of L-arginine supplementation on platelet indices in response to a high intensity interval exercise.

Ten healthy overweight young men (BMI=27 ± 1.2 kg/m2) participated voluntarily in this cross-over and double-blind study, and performed a high intensity interval exercise (HIIE) protocol with L-arginine supplementation or placebo, where, two trials were separated by seven days. In each session, the subjects consumed 0.075 g per kg body weight of supplement or placebo which was dissolved in 400 ml of water, and 90 minutes later, performed HIIE as 12 intervals of 3-minute on treadmill (activity: 1-min, 100% of vVO2max, recovery: 2-min, 40% of vVO2max). To measure platelet indices including mean platelet volume (MPV), platelet count (PLT), plateletcrit (PCT) and platelet distribution width (PDW), three blood samples were taken before supplementation and immediately before and after HIIE.

Regardless of the type of supplement, HIIE increased PLT and PCT by 29 and 31%, respectively (P < 001), but did not have a significant effect on MPV and PDW. Furthermore, consumption of L-arginine 90 min prior to HIIE, inhibited PCT (P = 0.043) but had no effect on PLT.

Intermittent nature and recovery periods in HIIE protocol did not significantly increase MPV and PDW in both sessions, which may be a reason for the safety of the HIIE. L-arginine supplementation prior to HIIE only reduced PCT, due to its inability to affect other indices, to achieve more accurate results further studies with more effective doses of supplementation are needed.

The results of the studies indicated that strenuous acute exercise can lead to increased inflammatory indices, muscle injury and decreased performance in athletes. Nevertheless, it has been suggested that the nutritional intervention may diminish inflammation and muscle cell damage. Hence, the aim of this investigation was to study the acute effect of ginkgo biloba extract on creatine kinase (CK) and lactate dehydrogenase (LDH) levels, as muscle soreness markers, and C- reactive protein (CRP) after high intensity interval training (HIIT) in active girls. In a quasi-experimental study 24 active girls (mean age: 24.06±3.43 years; weight: 57.56±6.03 kg; height: 159.98±4.87 cm and body mass index: 22.51±2.41 kg/m2) randomly assigned into two Ginkgo biloba supplement and placebo groups. Subjects in supplement group consume 160 mg/day of ginkgo biloba extract daily for 3 weeks while the placebo group received the same amount of placebo. All subjects of both groups underwent in high intensity interval exercise RAST (including two sets of 6 repetitions of two fast running 35 meters and with a maximum intensity performed after the rest interval of 10 seconds in each repetition) after 3weeks of supplementation. Venous blood samples were collected for assessment of CK, LDH and CRP indices at four stages. Data was analyzed by repeated measure ANOVA and Bonferroni post-hoc test at α ≤ 0.05. The results showed that the HIIT increased the levels of CK, LDH and CRP at the immediately and 24 hours after exercise in both placebo and supplement groups (p<0/05). Nevertheless, ginkgo biloba supplementation attenuated their increase of CK and CRP indicators following high intensity exercise compared to control groups (p<0/05). The results of this study indicated that ginkgo biloba supplementation can be effective in alleviates the inflammation and muscular damage by the HIIT in active girls.

The present study was designed to investigate the effects of L-Arginine supplementation on fat and carbohydrate metabolism during high intensity interval exercise (HIIE) in overweight individuals.

Ten male overweight students performed two HIIE trials including 10 intervals of 3 min encompassed 1 min running at 100% of vVO2max and 2 min active recovery at 40% of vVO2max. In each session subjects consumed either supplement or placebo 90 min prior to exercise. Before and after supplementation and immediately after exercise glucose, insulin, non-esterified free fatty acid (NEFA) and triglyceride were measured. Oxygen consumption and exhaled carbon dioxide were collected to calculate fat and carbohydrate oxidation.

There were no significant differences between two trials for glucose, insulin, NEFA, triglyceride and fat oxidation (P>0.05). However, carbohydrate oxidation rate was significantly different between two sessions (p < 0.05). In addition, glucose and carbohydrate oxidation were significantly increased following HIIE irrespective of L-Arginine supplementation (p < 0.05).

Based on the findings of present study it could be concluded that L-Arginine supplementation leads to increases in carbohydrate oxidation during HIIE in overweight men, but has no effect on resting at metabolism.

CGT sport supplement is combined of three creatine, glutamine and taurine supplement that respectively formed 50, 30 and 20 percent of the total content of supplementation. The aim of this study was to investigate the effect of CGT supplementation on response of markers of muscle and liver damage (creatine kinase, lactate dehydrogenase, alanine aminotransferase and aspartate aminotransferase) to high intensity interval exercise in trained men.

Nineteen trained men (age: 22.28±0.73 years; BMI: 22.35±1.66 kg/m2; fat percentage: 8.87±2.93 %) were randomly divided into two groups including CGT supplementation (n=9) and placebo (n=10). Supplementation group consumed CGT supplementation for 2 weeks up to 12 grams per day and placebo group consumed starch powder at same dose. Both groups performed HIIE protocol at pre and post-supplementation that contains the sequences. Blood samples were taken in 6 steps included before, immediately and 2 hours after the pre test, and the same steps in the post-test. The collected data were analyzed using descriptive and inferential statistics and significant level of p

Data analysis showed, creatine kinase and lactate dehydrogenase levels significantly increased immediately and two hours after the exercise in both supplement and placebo groups (p˂0.05). But there was no significant changes in alanine aminotransferase and aspartate aminotransferase levels. (p>0.05). CGT supplementation significantly decreased response of creatine kinase and lactate dehydrogenase to HIIE immediately and 2 hours after the activity (p˂0.05). However, CGT supplementation no significantly affected by changes in alanine aminotransferase and aspartate aminotransferase immediately and 2 hours after HIIE (p>0.05).

Generally, the results indicated that short-term CGT supplementation prevents from muscle damage induced by high intensity interval exercise.

The aim of this study was to determine the effect of upper body and lower body interval exercise on hemorheological factors. Twelve subjects (BMI=30±3 kg/m2) participated in this study. After determining VO2max for upper body and lower body, subjects performed the interval exercise for upper body and lower body in two separate sessions with one week intervening. Interval exercise included 2 minutes of exercise at 85% of VO2max and 4 min recovery at 45% of VO2max. Blood sample were taken before and immediately after exercise and were analyzed. The results showed that irrespective of the exercise type, exercise resulted in significant increases in hematocrit, plasma viscosity, red blood cell count, lactate, rigidity index (Tk) and a significant decrease in the fibrinogen (P<0.05) and no significant (P>0.05) changes in the blood viscosity, red blood cell aggregation, red blood cell deformability, hemoglobin, oxygen supply to tissue, rigidity index Tk. The comparisons of the changes for all variables including blood viscosity, hematocrit, hemoglobin, oxygen supply to tissue, red blood cell aggregation, red deformability, and rigidity index (Tk), lactate, fibrinogen and systolic blood pressure did not show any significant differences between two exercise protocols (P>0.05). However, changes of plasma viscosity in lower extremity and red blood cell count in upper extrimity were significantly different between two trials (P<0.05). It concluded that the acute exercise inducing changes in hemorheological variables, though, these changes are not related to exercise type and body parts involved in acute exercise.