Effects of a commercially available branched-chain amino acid-alanine-carbohydrate-based sports supplement on perceived exertion and performance in high intensity endurance cycling tests.

Background: Sports nutritional supplements containing branched-chain amino acids (BCAA) have been widely reported to improve psychological and biological aspects connected to central fatigue and performance in endurance exercise, although the topic is still open to debate. The aim of the present study was to determine whether the intake of a commercially available BCAA-based supplement, taken according to the manufacturer's recommendations, could affect the rating of perceived exertion (RPE) and performance indexes at the beginning (1d) and end of a 9-week (9w) scheduled high intensity interval training program, with an experimental approach integrating the determination of psychometric, performance, metabolic and blood biochemical parameters.

Methods: This was a randomized double-blind placebo-controlled study.

Post-Activation Potentiation Increases Recruitment of Fast Twitch Fibers: A Potential Practical Application in Runners.

To determine the relationship between fatigue and post-activation potentiation, we examined the effects of sub-maximal continuous running on neuromuscular function tests, as well as on the squat jump and counter movement jump in endurance athletes. The height of the squat jump and counter movement jump and the estimate of the fast twitch fiber recruiting capabilities were assessed in seven male middle distance runners before and after 40 min of continuous running at an intensity corresponding to the individual lactate threshold. The same test was then repeated after three weeks of specific aerobic training.

Muscular viscoelastic characteristics of athletes participating in the European Master Indoor Athletics Championship.

Purpose: To investigate how the viscoelastic characteristics of muscles (non-neural tone, elasticity and stiffness) vary as a function of age and gender in a sample of track and field master athletes. To compare these findings with data on related sedentary subjects in literature.

Methods: A total of 390 athletes (aged 35-99) were assessed during the European Master Athletics Indoor Championship 2016.

A simple method to analyze overall individual physical fitness in firefighters.

The aim of this study was to identify the main components that determine firefighters' level of physical fitness using a stair-climbing test. The age, weight, height, body fat, and VO(2max) of the firefighters were recorded before the trial, and percentage of heart rate reserve (%HRR) was recorded during the stair climbing. Nonlinear modeling of HRR time series and Principal Component Analysis (PCA) was applied to the data to isolate a small number of variables that quantify overall individual physical fitness.