Food restriction alters salivary cortisol and α-amylase responses to a simulated weightlifting competition without significant performance modification

ABSTRACT

The aim of this investigation was to evaluate the effect of a 6-day food restriction period on the physiological responses and performance of 11 high-level weightlifters. After a period of weight maintenance (T₂), they were assigned into two groups depending on whether they lost (Diet group, n = 6) or maintained their body weight (Control group, n = 5) during the course of those 6 days. An evaluation of performance and the measurement of salivary cortisol concentrations and salivary α-amylase (sAA) activity were performed during a simulated weightlifting competition which took place at T₂, after a 6-day period of food restriction (T₃). Dietary data were collected using a 6-day diet record. We noted a 41.8% decrease in mean energy intake during the dietary restriction period, leading to a 4.34% weight loss for the Diet group. Dietary restriction did not modify absolute performance levels, whilst a significant improvement was noted for the Control group. Furthermore, we noted a response of decreased salivary cortisol and increased sAA activity to the simulated competition stress at T₃ for the Diet group. These results may indicate that dietary reduction led to a dissociation of the hypothalamo-pituitary-adrenal axis and the sympatho-adreno-medullary system, which could impair training adaptations and absolute performance development.

KEYWORDS:

• Rapid weight loss
• physiological responses
• weightlifting
• simulated competitions

Acknowledgement

The authors are very grateful to the athletes for their participation and their commitment during the entire experiment.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The study was financially supported by the French Ministry of Sports (Ministère de la ville, de la Jeunesse et des Sports), the French National Institute of Sports, Expertise and Performance (INSEP) and the French Weightlifting Federation (Fédération Française d'Haltérophilie et de Musculation, FFHM).

Notes on contributors

Alexandre Durguerian

AD conceived and developed the study design, supervised the participants during the experiment, took photos of the meals, participated in data acquisition and interpretation and wrote the manuscript. EF conceived and developed the study design, participated in data interpretation and wrote the manuscript. CD analysed the saliva samples. CB conceived and developed the study design, supervised the participants during the experiment and participated in data acquisition. MC conceived and developed the study design and participated in data acquisition and interpretation. All authors have read and approved the final manuscript.

Edith Filaire

AD conceived and developed the study design, supervised the participants during the experiment, took photos of the meals, participated in data acquisition and interpretation and wrote the manuscript. EF conceived and developed the study design, participated in data interpretation and wrote the manuscript. CD analysed the saliva samples. CB conceived and developed the study design, supervised the participants during the experiment and participated in data acquisition. MC conceived and developed the study design and participated in data acquisition and interpretation. All authors have read and approved the final manuscript.

Catherine Drogou

AD conceived and developed the study design, supervised the participants during the experiment, took photos of the meals, participated in data acquisition and interpretation and wrote the manuscript. EF conceived and developed the study design, participated in data interpretation and wrote the manuscript. CD analysed the saliva samples. CB conceived and developed the study design, supervised the participants during the experiment and participated in data acquisition. MC conceived and developed the study design and participated in data acquisition and interpretation. All authors have read and approved the final manuscript.

Clément Bougard

AD conceived and developed the study design, supervised the participants during the experiment, took photos of the meals, participated in data acquisition and interpretation and wrote the manuscript. EF conceived and developed the study design, participated in data interpretation and wrote the manuscript. CD analysed the saliva samples. CB conceived and developed the study design, supervised the participants during the experiment and participated in data acquisition. MC conceived and developed the study design and participated in data acquisition and interpretation. All authors have read and approved the final manuscript.

Mounir Chennaoui

AD conceived and developed the study design, supervised the participants during the experiment, took photos of the meals, participated in data acquisition and interpretation and wrote the manuscript. EF conceived and developed the study design, participated in data interpretation and wrote the manuscript. CD analysed the saliva samples. CB conceived and developed the study design, supervised the participants during the experiment and participated in data acquisition. MC conceived and developed the study design and participated in data acquisition and interpretation. All authors have read and approved the final manuscript.