Sleep and Salivary Testosterone and Cortisol During a Short Preseason Camp: A Study in Professional Rugby Union

Abstract

Purpose: To examine changes in, and relationships between, sleep quality and quantity, salivary testosterone, salivary cortisol, testosterone-to-cortisol ratio (T:C), and self-reported muscle soreness during a residential-based training camp in elite rugby players. Methods: Nineteen male rugby players age 26.4 (3.9) years, height 186.0 (9.4) cm, and weight 104.1 (13.4) kg (mean [SD]) participated in this study. Wrist actigraphy devices were worn for 8 nights around a 4-d training camp (2 nights prior, during, and 2 nights after). Sleep-onset latency, sleep duration, sleep efficiency, and waking time were measured. Participants provided saliva samples during camp on waking and again 45 min later, which were then assayed for testosterone and cortisol levels. They also rated their general muscle soreness daily. Results: Little variation was observed for sleep quality and quantity or testosterone. However, significant differences were observed between and within days for cortisol, T:C, and muscle soreness (P < .001). Few relationships were observed for sleep and hormones; the strongest, an inverse relationship for sleep efficiency and T:C (r = −.372, P < .01). Conclusions: There may be no clear and useful relationship between sleep and hormone concentration in a short-term training camp context, and measures of sleep and testosterone and cortisol should be interpreted with caution because of individual variation. Alterations in hormone concentration, particularly cortisol, may be affected by other factors including anticipation of the day ahead. This study adds to our knowledge that changes in hormone concentration are individual and context specific.

Evolution of Research on Elite Adult Athlete Sleep: A Systematic Review

“…In only 12% of the studies the design of the articles was longitudinal and experimental [38,44,57,61], with the total research period between two to nine weeks, and in 32% the design was longitudinal and descriptive [22,26,30,32,35,[39][40][41][42][52][53][54][55]60], with a minimum and maximum period of two weeks [52][53][54] to two seasons [32], respectively. In 18% of the articles the design was cross-sectional and experimental [28,33,36,46,59,63,[65][66][67], and in 38% of the articles the design was cross-sectional and descriptive [2,21,23,24,27,31,37,45,[47][48][49][50][51]56,58,62,…”

“…The different instruments were used together in several studies, such as: Actigraphy and sleep diary [2,21,27,30,36,38,44,46 Table 1 of the supplementary material presents the 50 studies with the information: First author, year of publication, place of data collection, sample, performance level, and the instrument used to monitor sleep. There was a great continental disparity, with Oceania [2,24,25,30,32,[35][36][37][38][39]47,[49][50][51][52][53][54][55][56][57][58][59][60][61][62]67], responsible for more than 50% of the articles. Brazil [22,23,28,29,46], Japan [33,45,69] and Portugal [41][42][43]48] were the countries with more publications i...…”

“…A total of 2964 athletes was observed, with 1068 female athletes. The sample was composed only of women in 14% of the articles [2,41,42,48,51,55,66], while in 60% of the articles the sample was composed exclusively of men [22,[24][25][26][27][28][30][31][32][34][35][36][37][38][39][40]43,47,50,54,[56][57][58][59][60][61][63][64][65]67]. In 40% of the articles the sample was composed only of athletes with international performance [2,23,[26][27][28][29][30]32,33,38,40,45,…”

Does stress affect nonverbal engagement in teams? A case study in professional team sport

“…Conversely T:C showed its greatest magnitude decline in parallel with this. This study was conducted during a preseason live in training camp where players were uncertain as to what might be demanded of them so it is possible that the CAR was a function of anticipation stress, as seen previously (Serpell et al, 2018a), which reduced over the duration and experience of the camp. Given CAR appears to be influenced in a predictive manner in humans (e.g.…”

“…This may have affected retention of information and therefore subsequent training quality (Farrow and Robertson, 2017). Furthermore, it is known that testosterone and cortisol concentration is affected by circadian rhythm; that they typically decline as the day progresses (Serpell et al, 2018a(Serpell et al, , 2018b Nonverbal engagement in teams Strahorn et al, 2017). In addition, there was a speed and weights training session between the meeting and the team training session on day one, but not on day three.…”