Whole egg may have potential benefits for enhancing muscle mass, independent of its protein content. The yolk comprises ∼40% of the total protein in an egg, as well as containing several nonprotein nutrients that could possess anabolic properties (e.g., microRNAs, vitamins, minerals, lipids, phosphatidic acid and other phospholipids). Therefore, the purpose of this narrative review is to discuss the current evidence as to the possible effects of egg yolk compounds on skeletal muscle accretion beyond those of egg whites alone. The intake of whole egg seems to promote greater myofibrillar protein synthesis than egg white intake in young men. However, limited evidence shows no difference in muscle hypertrophy when comparing the consumption of whole egg versus an isonitrogenous quantity of egg white in young men performing resistance training. Although egg yolk intake seems to promote additional acute increases on myofibrillar protein synthesis, it does not seem to further enhance muscle mass when compared to egg whites when consumed as part of a high-protein dietary patterns, at least in young men. This conclusion is based on very limited evidence and more studies are needed to evaluate the effects of egg yolk (or whole eggs) intake on muscle mass not only in young men, but also in other populations such as women, older adults, and individuals with muscle wasting diseases.
Heitor O. Santos, Gederson K. Gomes, Brad J. Schoenfeld, and Erick P. de Oliveira
Thomas Birkedal Stenqvist, Anna Katarina Melin, Ina Garthe, Gary Slater, Gøran Paulsen, Juma Iraki, Jose Areta, and Monica Klungland Torstveit
The syndrome of Relative Energy Deficiency in Sport (RED-S) includes wide-ranging effects on physiological and psychological functioning, performance, and general health. However, RED-S is understudied among male athletes at the highest performance levels. This cross-sectional study aimed to investigate surrogate RED-S markers prevalence in Norwegian male Olympic-level athletes. Athletes (n = 44) aged 24.7 ± 3.8 years, body mass 81.3 ± 15.9 kg, body fat 13.7% ± 5.8%, and training volume 76.1 ± 22.9 hr/month were included. Assessed parameters included resting metabolic rate (RMR), body composition, and bone mineral density by dual-energy X-ray absorptiometry and venous blood variables (testosterone, free triiodothyronine, cortisol, and lipids). Seven athletes (16%) grouped by the presence of low RMR (RMRratio < 0.90) (0.81 ± 0.07 vs. 1.04 ± 0.09, p < .001, effect size 2.6), also showed lower testosterone (12.9 ± 5.3 vs. 19.0 ± 5.3 nmol/L, p = .020) than in normal RMR group. In low RMRratio individuals, prevalence of other RED-S markers (—subclinical—low testosterone, low free triiodothyronine, high cortisol, and elevated low-density lipoprotein) was (N/number of markers): 2/0, 2/1, 2/2, 1/3. Low bone mineral density (z-score < −1) was found in 16% of the athletes, all with normal RMR. Subclinical low testosterone and free triiodothyronine levels were found in nine (25%) and two (5%) athletes, respectively. Subclinical high cortisol was found in 23% of athletes while 34% had elevated low-density lipoprotein cholesterol levels. Seven of 12 athletes with two or more RED-S markers had normal RMR. In conclusion, this study found that multiple RED-S markers also exist in male Olympic-level athletes. This highlights the importance of regular screening of male elite athletes, to ensure early detection and treatment of RED-S.
James C. Morehen, Carl Langan-Evans, Elliot C.R. Hall, Graeme L. Close, and James P. Morton
Weight cycling is thought to increase the risk of obesity and cardiometabolic disease in nonathletic and athletic populations. However, the magnitude and frequency of weight cycling is not well characterized in elite athletes. To this end, we quantified the weight cycling practices of a male World Champion professional boxer competing at super middleweight (76.2 kg). Over a 5-year period comprising 11 contests, we assessed changes in body mass (n = 8 contests) and body composition (n = 6 contests) during the training camp preceding each contest. Time taken to make weight was 11 ± 4 weeks (range: 4–16). Absolute and relative weight loss for each contest was 12.4 ± 2.1 kg (range: 9.8–17.0) and 13.9% ± 2.0% (range: 11.3–18.2), respectively. Notably, the athlete commenced each training camp with progressive increases in fat mass (i.e., 12.5 and 16.1 kg for Contests 1 and 11) and reductions in fat-free mass (i.e., 69.8 and 67.5 kg for Contests 1 and 11, respectively). Data suggest that weight cycling may lead to “fat overshooting” and further weight gain in later life. Larger scale studies are now required to characterize the weight cycling practices of elite athletes and robustly assess future cardiometabolic disease risk. From an ethical perspective, practitioners should be aware of the potential health consequences associated with weight cycling.
Laura Swettenham and Amy E. Whitehead
The current study aimed to explore the perceptions of football academy coaches on their use of a novel reflective tool (Think Aloud [TA]) and to understand if this can support the development of knowledge within coaches. Eight male coaches (M age = 36) employed full time at a Category 1 football academy within the United Kingdom took part. All coaches attended a 2-hr workshop on the use of TA as a reflective tool, with the opportunity to practice TA while coaching. Participants were interviewed on their perceptions of TA as a reflective tool using a semistructured approach. Data were analyzed abductively, which allowed the generation of initial codes and the involvement of the triad of knowledge (professional, interpersonal, and intrapersonal knowledge), which has been adopted within coaching and identified as an approach to developing coaching expertise, within the analysis process. Findings suggest that all three types of knowledge can be developed through the use of TA, with subthemes identified within each type of knowledge: professional knowledge (player and coach development and session design), interpersonal knowledge (communication and relationships), and intrapersonal knowledge (biases, self-awareness, and reflection). This research offers a novel perspective on coach development through the implementation of TA, with potential to support the development of coaching knowledge and expertise.
Steve M. Smith, Hazel Brown, and Stewart T. Cotterill
The psychological factors that influence performance in the practice environment, where competitive athletes engage in deliberate practice, have recently been given specific research attention. The current study employed an action research approach to implement the practice environment model as an education strategy to increase the practice performance of players in a U.K. basketball academy team over a 20-week period. The aim of the study was to evaluate the effect of the education strategy on practice performance. The team competed nationally and consisted of the head coach, the assistant coach, and 18 male players aged 16–19 years. Data were collected through focus groups, joint semistructured interviews, field observations, and a practice environment model web-based questionnaire. Qualitative data were analysed using thematic narrative analysis and the Friedman test analysed quantitative data. Quantitative results suggested that the education strategy decreased perceptions of stress and increased effort, preparation activities, and teammate support. Qualitative results provided an in-depth narrative of the environmental changes undertaken to improve practice performance. Discussion focuses on the key strategies of effort and control, performance expectations, team drive, positive communication, and preparation. This study is the first to apply the practice environment model to a real-world sporting domain.
Hassan Gharayagh Zandi, Sahar Zarei, Mohammad Ali Besharat, Davoud Houminiyan sharif abadi, and Ahmad Bagher Zadeh
Coaching has often been viewed as a context within which coaches operate to largely bring about changes in athlete’s performance and flourishing. One key factor to successful outcomes in coaching is the quality of the relationship between coaches and athletes. The coach–athlete relationship is at the heart of coaching; however, limited studies have been conducted on its antecedents. The aim of this study was to investigate the relationship between coaches’ forgiveness and perceived relationship quality toward their athletes through verifying the mediating role of interpersonal behaviors of coaches. A total of 270 Iranian coaches participated in the survey, and the data sets were analyzed using structural equation modeling. Results revealed that forgiveness positively predicted the coaches’ perceived relationship quality with their athletes, and this pathway was mediated by the coaches’ interpersonal behaviors.
Jeemin Kim, Katherine A. Tamminen, Constance Harris, and Sara Sutherland
Athletes often upregulate and downregulate pleasant or unpleasant emotions to feel or perform better (i.e., for hedonic or instrumental reasons). In addition to athletes regulating their own emotions, interpersonal emotion regulation (IER) also occurs in sports, wherein individuals attempt to regulate the emotions of others. Although previous research has examined IER between teammates, studies have rarely considered coaches’ efforts to regulate athletes’ emotions. The current mixed-method study explored coaches’ beliefs about athletes’ emotions and engagement in IER. Analysis of quantitative survey data (N = 208) and qualitative interview data (n = 10) from competitive level coaches (M age = 44.0 ± 13.2 years) revealed that coaches perceived both benefits and detriments of various emotions, and coaches’ beliefs about emotions influenced the ways they attempted to regulate athletes’ emotions. Most coaches reported frequently engaging in affect-improving IER. Although the coaches generally opposed the idea of intentionally worsening athletes’ emotions, sometimes their feedback to athletes had the effect of worsening their emotions. Coaches also emphasized the need to consider athletes’ individual differences when engaging in IER. The current findings highlight the relevance of coaches’ IER, suggest several directions for future research, and offer useful considerations for coaches and coach education programs.
Danielle Peers, Lindsay Eales, Kelvin Jones, Aidan Toth, Hernish Acharya, and Janice Richman–Eisenstat
The purpose of this study was to assess the safety and meaningfulness of a 15-week recreational dance and singing program for people with neuromuscular conditions. Within a transformative mixed-methods design, pulmonary function tests, plethysmography through wearable technology (Hexoskin vests), individualized neuromuscular quality-of-life assessments (version 2.0), and semistructured interviews were used. The interviews were analyzed through inductive, semantic thematic analysis. Although the sample sizes were small (six people with neuromuscular conditions), the authors found no evidence of safety concerns. There was evidence of respiratory improvements and reported improvements in swallowing and speech. The most notable quality-of-life changes included improvements related to weakness, swallowing, relationships, and leisure. The participants shared that the program offered meaningful social connection and embodied skills and safe and pleasurable physical exertion. The authors learned that recreational singing and dancing programs could be a safe and deeply meaningful activity for those with neuromuscular conditions that impact respiration.
Rebecca L. Jones, Trent Stellingwerff, Paul Swinton, Guilherme Giannini Artioli, Bryan Saunders, and Craig Sale
This study determined the influence of a high- (HI) versus low-intensity (LI) cycling warm-up on blood acid-base responses and exercise capacity following ingestion of sodium bicarbonate (SB; 0.3 g/kg body mass) or a placebo (PLA; maltodextrin) 3 hr prior to warm-up. Twelve men (21 ± 2 years, 79.2 ± 3.6 kg body mass, and maximum power output [W max] 318 ± 36 W) completed a familiarization and four double-blind trials in a counterbalanced order: HI warm-up with SB, HI warm-up with PLA, LI warm-up with SB, and LI warm-up with PLA. LI warm-up was 15 min at 60% W max, while the HI warm-up (typical of elites) featured LI followed by 2 × 30 s (3-min break) at W max, finishing 30 min prior to a cycling capacity test at 110% W max. Blood bicarbonate and lactate were measured throughout. SB supplementation increased blood bicarbonate (+6.4 mmol/L; 95% confidence interval, CI [5.7, 7.1]) prior to greater reductions with HI warm-up (−3.8 mmol/L; 95% CI [−5.8, −1.8]). However, during the 30-min recovery, blood bicarbonate rebounded and increased in all conditions, with concentrations ∼5.3 mmol/L greater with SB supplementation (p < .001). Blood bicarbonate significantly declined during the cycling capacity test at 110%W max with greater reductions following SB supplementation (−2.4 mmol/L; 95% CI [−3.8, −0.90]). Aligned with these results, SB supplementation increased total work done during the cycling capacity test at 110% W max (+8.5 kJ; 95% CI [3.6, 13.4], ∼19% increase) with no significant main effect of warm-up intensity (+0.0 kJ; 95% CI [−5.0, 5.0]). Collectively, the results demonstrate that SB supplementation can improve HI cycling capacity irrespective of prior warm-up intensity, likely due to blood alkalosis.