Purpose: To evaluate the effect of acute ingestion of green tea polyphenols (GTP) on blood markers of oxidative stress and muscle damage in soccer players exposed to intense exercise.Methods: This randomized, double-blinded study was conducted on 16 players during a general preparation period, when all athletes participated in a strength-training program focused on the development of strength endurance. After ingestion of a single dose of GTP (640 mg) or placebo, all athletes performed an intense muscle-endurance test consisting of 3 sets of 2 strength exercises (bench press, back squat) performed to exhaustion, with a load at 60% 1-repetition maximum and 1-min rests between sets. Blood samples were collected preexercise, 5 min after the muscle-endurance test, and after 24 hr of recovery. Blood plasma was analyzed for the concentrations of thiobarbituric acid–reacting substances (TBARS), uric acid (UA), total catechins, total antioxidant status (TAS), and activity of creatine kinase (CK); at the same time, erythrocytes were assayed for the activity of superoxide dismutase (SOD).Results: In both groups, plasma TBARS, UA, and TAS increased significantly postexercise and remained elevated after a 24-hr recovery period. SOD activity in erythrocytes did not change significantly in response to the muscle-endurance test, whereas in both groups plasma CK activity increased significantly after 24 hr of recovery. Acute intake of GTP cased a slight but significant increase in total plasma catechins. However, GTP was found not to exert a significant effect on measured parameters.Conclusions: Acute ingestion of GTP (640 mg) does not attenuate exercise-induced oxidative stress and muscle damage.
Sphingosine-1-phosphate (S1P) regulates cardiovascular function and plays an important role in muscle biology. We have previously reported that cycling exercise increased plasma S1P. Here, we investigated the effect of exercise duration and intensity on plasma and skeletal muscle S1P levels.
Background: Systematic physical activity can permanently prevent disadvantageous developments in the human body. This is very important especially for women, for whom the maintenance of a lean body in good shape is sometimes a primary consideration. However, in most cases, this activity is taken randomly and does not produce the desired effects such as reducing body fat. The purpose of the study was to evaluate changes in female body composition induced by 12 weeks of swimming training compared to sedentary controls. Methods: Training sessions occurred three times per week (60 min/session). Height, body mass, and waist/hip circumference and waist/hips ratio (WHR) were measured. Body cell mass (BCM), total body water (TBW), extracellular (ECW) and intracellular water (ICW), fat mass (FM), lean mass (FFM), and muscle mass (MM) were measured using bioelectrical impedance (pre/post). Results: Training elicited decreases in hip circumference and increase in WHR. No changes were recorded in BCM, TBW, ECW, ICW, FM, FFM, and MM. Controls experienced decreases in values of BCM, ICW, and MM and increases in ECW. Conclusion: The applied swimming training did not significantly affect the body composition parameters. Inactivity also triggered a tendency toward unhealthy movement of water from the intracellular to extracellular space.
Importance: Physical activity is recognized as one of the most important tools in the management of gestational diabetes mellitus (GDM). Objective: The aim of this review was to compare and analyze regular prenatal exercise programs and examine their effectiveness in the prevention of GDM. Evidence Acquisition: The following databases were used: Academic Search Complete, Health Source–Consumer Edition, Health Source–Nursing/Academic Edition, Master File Premier, MEDLINE, and SportDiscus with full text. The inclusion criteria were as follows: a randomized study, regular training program throughout pregnancy, and supervised by a prenatal activity specialist. Results: The 10 articles selected for the review were divided into 2 groups. The first group comprised 2 studies presenting successful interventions in the prevention of GDM, whereas the second group included 8 articles with no statistically significant effects of the training programs in GDM prevention. Beginning an exercise program at early stages of the pregnancy and high adherence were common features of the effective programs. Conclusions: When designing and carrying out the program, the beginning of the intervention and adherence should be considered. To increase adherence, the program should be attractive and it should meet the participants' needs. Relevance: This review might be used for identifying factors deciding whether an exercise program is an effective intervention to prevent the development of GDM. Moreover, it might also prove useful in the preparation of future guidelines for designing and implementing regular exercise programs effective in preventing GDM in pregnant women by gynecologists, obstetricians, midwives, trainers, and prenatal specialists. Target Audience: Obstetricians and gynecologists, family physicians. Learning Objectives: After participating in this activity, physicians should be better able to compare and analyze regular prenatal exercise programs; identify the most effective exercise programs in the prevention of GDM; distinguish factors decisive in gravid participants' involvement in regular physical activity sessions; and prepare for preparation of the future guidelines regarding regular exercise programs effective in preventing GDM.