Abstract
BACKGROUND
The purpose of the present study was to examine the effects of time-of-day-strength training on plasma testosterone (T) and cortisol (C) concentrations in male amateur athletes.
METHODS
Forty-five male athletes (age, 21.2±0.3 years; height, 1.75±0.14 m; weight, 72±1.52 kg) participated in the present study. They were subjected to strength training of the knee extensor and flexor muscles. Following this, they were randomly assigned into three groups: morning strength training group (MSTG, 07:00-08:00 hours, N.=15), afternoon strength training group (ASTG, 16:00-17:00 hours, N.=15) and morning and afternoon strength training group (MASTG, 07:00-08:00 and 16:00-17:00 hours, N.=15). The concentration of T and C for each athlete was collected in all three conditions in the morning, noon and afternoon, before and after 8 weeks of strength training. The effects of group, time of the day and pre- to post-training were verified by a 3-way analysis of variance with repeated measures.
RESULTS
Our results indicate that strength training induces an increase of plasma T/C ratio in both groups of athletes who have always trained for only one session per day mainly in the afternoon compared with the MASTG (P<0.05). However, a reduction of the plasma T/C ratio was observed in the athletes who have always trained successively in the morning and in the afternoon (P<0.05). Plasma T/C ratio exhibit circadian rhythmicity in all groups showing a low level in the morning, whereas in the afternoon an increased value was more noted (P<0.05).
CONCLUSIONS
From an applied perspective, this study suggests that amateur athletes should train at the afternoon to maximize their performance gain.
The purpose of the present study was to examine the effects of time-of-day-strength training on plasma testosterone (T) and cortisol (C) concentrations in male amateur athletes.
METHODS
Forty-five male athletes (age, 21.2±0.3 years; height, 1.75±0.14 m; weight, 72±1.52 kg) participated in the present study. They were subjected to strength training of the knee extensor and flexor muscles. Following this, they were randomly assigned into three groups: morning strength training group (MSTG, 07:00-08:00 hours, N.=15), afternoon strength training group (ASTG, 16:00-17:00 hours, N.=15) and morning and afternoon strength training group (MASTG, 07:00-08:00 and 16:00-17:00 hours, N.=15). The concentration of T and C for each athlete was collected in all three conditions in the morning, noon and afternoon, before and after 8 weeks of strength training. The effects of group, time of the day and pre- to post-training were verified by a 3-way analysis of variance with repeated measures.
RESULTS
Our results indicate that strength training induces an increase of plasma T/C ratio in both groups of athletes who have always trained for only one session per day mainly in the afternoon compared with the MASTG (P<0.05). However, a reduction of the plasma T/C ratio was observed in the athletes who have always trained successively in the morning and in the afternoon (P<0.05). Plasma T/C ratio exhibit circadian rhythmicity in all groups showing a low level in the morning, whereas in the afternoon an increased value was more noted (P<0.05).
CONCLUSIONS
From an applied perspective, this study suggests that amateur athletes should train at the afternoon to maximize their performance gain.
| Original language | English |
|---|---|
| Pages (from-to) | 67-78 |
| Number of pages | 12 |
| Journal | Medicina Dello Sport |
| Volume | 72 |
| Issue number | 1 |
| Early online date | 4 Mar 2019 |
| DOIs | |
| Publication status | Published - Mar 2019 |
Keywords
- Resistance training
- Testosterone
- Hydrocortisone
- Circadian rhythm
- Athletes