Variation of explosive force at different times of day
Journal Title: Biology of Sport - Year 2011, Vol 28, Issue 1
Abstract
AIM: The purpose of this study was to compare the explosive force and electromyographic (EMG) activity at three different times of the day. METHODS: Thirty healthy subjects took part in the study, and carried out two maximum isometric voluntary knee extensions to measure explosive force, through contractile impulse (CI) and rate of force development (RFD), and myoelectric signals from quadriceps muscles in the following periods: 07:30-09:30, 13:30-15:30 and 19:30-21:30 (called morning, afternoon and night respectively), on three non-consecutive days. RESULTS: The body temperature was lower in the morning than in the afternoon and night periods. The explosive force, evaluated through contractile impulse (CI) and rate of force development (RFD), was greater at night than in the morning, without differences in the myoelectric signal. CONCLUSION: The ability to produce explosive force varies throughout different times of the day without variation in muscular recruitment, indicating that peripheral and not neural mechanisms could be responsible for this variation.
Authors and Affiliations
R Pereira, M Machado, W Ribeiro, A. K. Russo, A. de Paula, R. A. Lazo-Osório
Keywords
Related Articles
- EP ID EP59034
- DOI -
- Views 97
- Downloads 0
TARGET-DIRECTED RUNNING IN GYMNASTICS: THE ROLE OF THE SPRINGBOARD POSITION AS AN INFORMATIONAL SOURCE TO REGULATE HANDSPRINGS ON VAULT
Empirical evidence highlights the role of visual information to control gymnastics vaulting and thus neglects a stereotyped approach run. However, there is no evidence on which informational source this regulation is bas...
Cannabinoids cases in polish athletes
The aim of this study was to investigate the number of cases and the profiles of Polish athletes who had occasionally been using marijuana or hashish throughout the period of 1998-2004, with respect to: sex, age, and dis...
EXERCISE MYOPATHY: CHANGES IN MYOFIBRILS OF FAST-TWITCH MUSCLE FIBRES
The purpose of the present study was to determine the relationships between the changes of myofibrils in fast-twitch oxidative-glycolytic (type IIA) fibres and fast-twitch glycolytic (type IIB) muscle fibres, protein syn...
Application of the allometric scale for the submaximal oxygen uptake in runners and rowers
Background: The aim of the current study was to determine the allometric exponents for runners and rower’s metabolic cost, while also verifying the relation of performance with and without the allometric application. Met...
The influence of individualizing physical loads on speed, creatine kinase activity and lactate dehydrogenase in football players.
Introduction: One of the most important training problems in: contemporary football is speed preparation of a player for the season and the ability of keeping it on the same, relatively high level throughout the starting...