The effects of acute consumption of carbohydrate-protein supplement in varied ratios on CrossFit athletes' performance in two CrossFit exercises: a randomized cross-over trial.

BACKGROUND: CrossFit is becoming popular over the past few years, and various supplementation ways have been utilized by exercise physiologists to enhance CrossFit athletes' performance. This study aimed to evaluate the effects of consuming preworkout carbohydrate-protein supplements on CrossFit athletes' performance. METHODS: Well-trained CrossFit athletes (8 men; 25.62±3.02 years) were randomized to a single-blind, placebo controlled, crossover design (7-day washout) to performed six bouts of two CrossFit workouts: Fight Gone Bad (FGB) and Cindy (CI). One hour and immediately before the onset of each bout, the subjects consumed carbohydrate-protein supplement in two ratios (2:2 or 3:1) or placebo (P): FGB+2:2, FGB+3:1, FGB+P, CI+2:2, CI+3:1, and CI+P. To value the differentiation in performances, the performed each subject repetitions in FGB and CI were recorded in the bouts. RESULTS: Repeated measure analysis of variance was used to analyze the data, and the level of significance set for the study was P≤0.05. No significant difference was observed in the total number of repetitions performed in FGB (P=0.275) or CI (P=0.789) workouts in supplements and placebo groups. CONCLUSIONS: These results indicate that acute consumption of preworkout carbohydrate-protein supplement may not enhance the CrossFit athletes' performance in FGB and CI workouts.

Response of coagulation and anti-coagulant factors of elite athletes following acute resistance and high-intensity interval training.

BACKGROUND: Blood coagulation and fibrinolysis include two vital physiological systems, which are regulated by a balance between activators and inhibitors. The aim of this study is to survey the response of coagulation and anticoagulant factors following acute resistance and high-intensity interval exercises. METHODS: This is an experimental study. The statistical sample was an elite group of karate males (aged 22.10±2.76 years, height 175.80±5.43 cm, mass 74.30±9.06 kg, body mass index 23.94±2.08 kg/m2, body fat 16.36±4.42 percent, maximal oxygen uptake 58.77±2.47 mL/kg/min) who voluntarily participated in the study. Before and after each exercise, blood sampling was carried out in order to measure plasma volume changes, fibrinogen, factor VIII, prothrombin time, partial thromboplastin time, platelet count, mean platelet volume and C-reactive protein. RESULTS: Decrease in plasma volume and fibrinogen following interval exercise was significantly higher than that of resistance exercise. The increase in Factor VIII and decrease in C-reactive protein and fibrinogen following interval exercise was considerably greater than after resistance exercise. Following each exercise, the decrease in prothrombin time, partial thromboplastin time and also increase in platelet count was significant. CONCLUSIONS: It can be concluded that high-intensity interval exercise via increase in coagulation process and fortification of fibrinolysis system induces optimal coagulation and fibrinolysis balance; it seems that the decrease in anticoagulant process is essential for this balance.

Dynamic Postural Control in Female Athletes and Nonathletes After a Whole-Body Fatigue Protocol.

Baghbani, F, Woodhouse, LJ, and Gaeini, AA. Dynamic postural control in female athletes and nonathletes after a whole-body fatigue protocol. J Strength Cond Res 30(7): 1942-1947, 2016-Postural control is a crucial element in regular training of athletes, development of complex technical movement, and injury prevention; however, distributing factor of the postural control such as fatigue has been neglected by athletic trainers in novice and inexperienced athletes. The objective of this study was to compare changes in dynamic postural control of young female athletes and nonathletes after a fatigue protocol. Thirty females (15 athletes and 15 nonathletes) with no orthopedic problems were recruited to participate in this study. All participants completed the pre-SEBT (star excursion balance test) in 8 directions at baseline; then, they performed a 20-minute fatigue protocol after which post-SEBT was measured. Rating of perceived exertion was measured using the Borg scale immediately before, mid-way through (i.e., after the third station), and after performing the fatigue protocol (i.e., immediately before the post-SEBT). Female nonathlete groups had significant differences in dynamic balance performance after fatigue in the medial, posteromedial, and posterior directions (p < 0.01) measured by SEBT. Athletes, however, showed no significant changes after the fatigue protocol. Our results indicates the importance of evaluation and monitoring of dynamic postural control of the novice with progressing the exercise time. Our findings could also help coaches to develop trainings focused on the 3 directions of medial, posteromedial, and posterior directions and aimed at exercises increasing fatigue resistance.