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Jockeys are unique given that they make weight daily and, therefore, often resort to fasting and dehydration. Through increasing daily food frequency (during energy deficit), we have reported short-term improvements in jockey’s body composition. While these changes were observed over 6–12 weeks with food provided, it is unclear whether such improvements can be maintained over an extended period during free-living conditions. We, therefore, assessed jockeys over 5 years using dual X-ray absorptiometry, resting metabolic rate, and hydration measurements. Following dietary and exercise advice, jockeys reduced fat mass from baseline of 7.1 ± 1.4 kg to 6.1 ± 0.7 kg and 6.1 ± 0.6 kg (p p p p = .009) and 87% (p = .003) at Years 1 and 5, alongside regular lunch from 35% to 92% (p p

Purpose: An understanding of an athlete’s total daily energy expenditure (TEE) is necessary to inform nutritional strategies, particularly where daily training and competitive demands are highly variable. This observational case series assessed the TEE of elite tennis players during high-level competition. Methods: Senior female singles participants (FS: n = 3; 21 [1] y; ranked Women’s Tennis Association [WTA] top 125–375), an FS junior (n = 1; 16 y; ranked WTA top 350), and a men’s doubles player (n = 1; 26 y; ranked Association of Tennis Professionals [ATP] top 5) were assessed for TEE (using the doubly labeled water method) during a 9- to 14-day period, which included training, Wimbledon Championships, WTA/ATP International Tournaments, Junior/Senior International Tennis Federation, and Wimbledon Junior Championships. One female (FS3) did not exercise from day 4 following injury. Results: TEE for men’s doubles was 4586 kcal·d−1 (67 kcal·kg−1 fat-free mass [FFM]; daily activity 98 [74] min). Noninjured adult female participants’ TEEs were 3396 and 3948 kcal·d−1 (66 and 81 kcal·kg−1 FFM; daily activity durations were 139 [84] min and 150 [66] min, respectively), while TEE for the injured athlete was 2583 kcal·d−1 (45.7 kcal·kg−1; daily nonexercise activity duration was −1 (78.2 kcal·kg−1 FFM; daily activity of 131 [66] min). Conclusion: This observational case series positions tennis as a highly energetically demanding sport with variability evident between individuals (ie, TEE between 60 and 90 kcal·kg−1 FFM). Accordingly, nutritional strategies that promote sufficient energy availability should be emphasized with individual variability suitably assessed prior to prescription.

Academy soccer players frequently train in the evening (i.e. 1700-2000 h), hence limited time to nutritionally prepare and recover due to schooling, travel and sleep schedules. Accordingly, we assessed timing and quantity of energy intake in the pre-training and post-training period. Over a 3-day in-season training period, male players (n=48; n=8 from under (U) 12, 13, 14, 15/16, 18 and 23 players) from an English Premier League academy self-reported dietary intake and physical activity levels (via the remote food photography method and activity diary, respectively) in the four hours pre- and post-training. Timing of pre-training energy intake ranged from 40 ± 28 mins (U15/U16 players) to 114 ± 71 mins (U18) before training and mean carbohydrate (CHO) intake ranged from 0.8±0.4 g.kg-1 (U23) to 1.5±0.9 g.kg-1 (U12). Timing of post-training energy intake ranged from 39 ± 27 mins (U14) to 70 ± 84 mins (U23) and mean CHO intake ranged from 1.6±0.8 g.kg-1 (U12) to 0.9±0.5 g.kg-1 (U14). In contrast to CHO, all age groups consumed sufficient protein intake in the post-training period (i.e.0.3 g.kg-1). We conclude academy soccer players habitually practice sub-optimal fuelling and recovery strategies, the consequence of which could impair growth, maturation and physical performance.

Total daily energy expenditure (“total expenditure”, MJ/d) reflects daily energy needs and is a critical variable in human health and physiology, yet it is unclear how daily expenditure changes over the life course. Here, we analyze a large, globally diverse database of total expenditure measured by the doubly labeled water method for males and females aged 8 days to 95 yr. We show that total expenditure is strongly related to fat free mass in a power-law manner and identify four distinct metabolic life stages. Fat free mass-adjusted daily expenditure accelerates rapidly in neonates (0-1yr) to ~46% above adult values at ~1 yr, declines slowly throughout childhood and adolescence (1-20 yr) to adult levels at ~20 yr, remains stable in adulthood (20-60 yr) even during pregnancy, and declines in older adults (60+ yr). These changes in total expenditure shed new light on human development and aging and should help shape nutrition and health strategies across the lifespan.

This case study follows a professional internationally capped female soccer player's two-year journey from eumenorrhea, through injury, to amenorrhea, and the challenges faced by the player and nutritionist. The two years are split into three sections: (1) longitudinal profiling of the player, (2) nutrition to support her return from injury, and (3) investigation into the observed secondary amenorrhea. The cause of amenorrhea was investigated through the assessment of energy availability via doubly labelled water, remote food photography, blood biomarkers and resting metabolic rate. Despite having secondary amenorrhea and anovulatory cycles, the player did not have low energy availability. This study shows the importance for practitioner's, particularly nutritionists, to not assume that all menstrual irregularities are caused by low energy availability and could be caused by a combination of factors (e.g. clinical, physiological, and psychological), which requires a multi-disciplinary investigation and intervention team. This study also showed that education needs to be provided about menstrual health to elite female soccer players as the player (i) believed that not having a period was beneficial for performance and unsure of possible health implications; (ii) was convinced that a one-day bleed indicated a regular menstrual cycle; and (iii) was reluctant to waste the practitioners time discussing menstrual issues and was nervous of finding out if she had an actual health issue. It is therefore crucial that players feel comfortable in discussing their menstrual status with practitioners to support their performance and long-term health.

Gastrointestinal symptoms are abundant among athletes engaging in endurance exercise, particularly when exercising in increased environmental temperatures, at higher intensities, or over extremely long distances. It is currently thought that prolonged ischemia, mechanical damage to the epithelial lining, and loss of epithelial barrier integrity are likely contributors of gastrointestinal (GI) distress during bouts of endurance exercise, but due to the many potential causes and sporadic nature of symptoms this phenomenon has proven difficult to study. In this review, we cover known factors that contribute to GI distress symptoms in athletes during exercise, while further attempting to identify novel avenues of future research to help elucidate mechanisms leading to symptomology. We explore the link between the intestinal microbiome, the integrity of the gut epithelia, and add detail on gut hormone and peptide secretion that could potentially contribute to GI distress symptoms in athletes. The influence of nutrition and dietary supplementation strategies are also detailed, where much research has opened up new ideas and potential mechanisms for understanding gut pathophysiology during exercise. The etiology of gastrointestinal symptoms during endurance exercise is multi-factorial with neuroendocrine, microbial, and nutritional factors likely contributing to specific, individualized symptoms. Recent work in previously unexplored areas of both microbiome and gut peptide secretion are pertinent areas for future work, and the numerous supplementation strategies explored to date have provided insight into physiological mechanisms that may be targetable to reduce the incidence and severity of gastrointestinal symptoms in athletes.

Purpose: To audit hormonal contraceptive use and associated symptomology in elite women’s soccer in England. Methods: Seventy-five elite women’s soccer players from the Women’s Super League (WSL) completed a questionnaire to assess: hormonal contraceptive (HC) use or non-use, reasons for initiation and discontinuation and the symptoms experienced by HC and non-HC users. Results: Twenty-eight per cent reported current HC use, with 43% having used HCs previously. Combined HCs accounted for 62% of total usage, with progestin-only HCs making up the remainder. Eighty-six per cent pre-empted negative symptoms before commencing HCs, with 38% experiencing adverse symptoms. Negative symptoms were most common in progestin-only HC users (63%). Eighty-six per cent reported benefits associated with HC usage include pain management and the ability to predict or control their cycles. Six non-HC users reported amenorrhea, with one medically diagnosed. Negative MC-related symptoms were reported by 74%, with 4% unable to train due to these symptoms. Unfavorable symptoms typically occurred during the first days of menstruation (59%). Conclusion: Most WSL players do not currently use HCs (72%). Most HC users reported benefits of HC usage, whilst most non-HC users reported negative symptoms especially around menstruation. Practitioners should track players' MCs to help minimise discomfort and maximise performance.

We quantified on pitch external loading of English Premier League (EPL) academy soccer players (n=76; U12-U18 age groups) over an entire competitive season. Mean accumulative weekly duration and total distance, respectively, was similar in the U12 (329±29 min; 19.9±2.2 km), U13 (323±29 min; 20.0±2.0 km) and U14 (339±25 min; 21.7±2.0 km; P>0.05 for all comparisons) age-groups, though all teams were less than U15 (421±15 min; 26.2±2.1 km), U16 (427±20 min; 25.9±2.5 km) and U18 (398±30 min; 26.1±2.6 km) players (P0.05 for all pairwise comparisons) though all squads were less than U15 (657±242 m and 49±98 m), U16 (749±152 m and 95±55 m) and U18 (979±254 m and 123±56 m) age-groups (P

The assessment of total energy expenditure (TEE) is imperative to ensure appropriate fuelling during competition and training, although the current lack of TEE research in para sport make the prescription of nutritional strategies challenging. This study aimed to assess TEE of an elite wheelchair tennis (WT) player during training and competition of the highest level. One male WT player (age 23.6 years; career high World No. 1; body mass 65.7 kg; VO2max, 45.3 ml.kg−1.min−1) participated. Prior to the assessment, VO2max and maximum heart rate, resting metabolic rate, 10 m sprint speed and upper body skinfold measurements were made. Doubly labelled water assessed TEE during a 19-day period which included the Wimbledon Championships (5 days-3 matches), training (8 days) and the British Open (BO) (6 days-7 matches). Throughout data collection, the participant continued their usual training and preparation. During Wimbledon, TEE was 3118 kcal·d−1: 60.3 kcal·kg−1 FFM: PAL 2.0 and during BO was 3368 kcal·day−1: 65.1 kcal·kg−1 FFM: PAL 2.2. Mean daily activity was 124 mins and 132 mins, respectively. During training, TEE was 3177kcal·day-1: 61.4kcal·kg-1 FFM: PAL 2.0: mean daily activity was 138 mins. These findings show the TEE of an elite WT player captured during a period of training and high-level competition, alongside data outlining the physiological profile of a world-class para-athlete.

La guia CONSORT (CONsolidated Standards Of Reporting Trials)de 2010 (http://www.consort-statement.org/consort-2010) fuedesarrollada para mejorar el informe de ensayos clinicoscontrolados aleatorios de grupos paralelos, por lo que elcumplimiento de los estandares establecidos se puede demostrarmediante la cumplimentacion de la lista de chequeo CONSORT20101. Las principales revistas medicas han respaldado estainiciativa, que sin duda ha mejorado la realizacion y el informe deresultados de la investigacion clinica y sanitaria. La investigacionen el campo de la nutricion deportiva y el metabolismo delejercicio se beneficiara de estandares similares, pero comunmenteutiliza disenos de investigacion diferentes a los ensayos clinicos degrupos paralelos, como los experimentos cruzados.Se ha publicado recientemente una ampliacion de CONSORT queaborda ensayos cruzados aleatorios2, con una lista de verificacionrevisada que se centra en cuestiones de primera relevancia paraensayos clinicos que abordan tratamientos medicos o deasistencia medica. Sin embargo, estas cuestiones especificas de losensayos clinicos, pueden tener una relevancia diferente, cuando seconsideran en relacion con los experimentos mecanicistas,estrictamente controlados, realizados en laboratorio, que sonhabituales en la ciencia del ejercicio. Por ejemplo, los disenoscruzados pueden implicar efectos de orden entre evaluaciones; enlos ensayos clinicos, esto suele ocurrir con mayor frecuenciadebido al tratamiento o la intervencion en si, lo que requiere unintervalo de lavado suficiente, antes de repetir las evaluaciones.Por el contrario, la tendencia en la investigacion sobre nutriciondeportiva, se relaciona comunmente con la evaluacion en simisma, que a menudo, tiende a ser mas invasiva o exigente para elparticipante, que una instantanea sobre su estado de salud. Dehecho, las pruebas fisicas de rendimiento humano sonparticularmente propensas a efectos de aprendizaje o fatiga eincluso algunas adaptaciones fisicas pueden persistir durantesemanas o meses despues del primer test. Por ejemplo, eldenominado “efecto de intentos repetidos”, que describe como unasola exposicion a un ejercicio fisico desacostumbrado que producedano muscular puede inducir una profunda y duradera proteccionante ejercicios similares en el futuro3,4. Los participantes enensayos de ejercicio tambien pueden ser atletas de elite, cuyosniveles habituales de actividad fisica (y dieta) pueden mostrarvariaciones profundas a lo largo del tiempo (es decir,periodizacion), lo que complica aun mas la interpretacion deestudios longitudinales.La lista de chequeo PRESENT (Proper Reporting of Evidence inSport & Exercise Nutrition Trials) 2020 (Ver Anexo), por tanto, seha adaptado de la guia CONSORT para abordar especificamente lacombinacion unica de desafios y oportunidades que enfrentan losinvestigadores dentro de los amplios campos de la nutriciondeportiva y el metabolismo del ejercicio. El presente documentocomplementa y desarrolla la lista de verificacion CONSORT alponer enfasis y proveer ejemplos comunes o de mayor relevanciapara la investigacion en esta area tematica. La lista decomprobacion PRESENT 2020 se diseno teniendo en cuenta lanecesidad de minimizar a los autores la sobrecarga que suponeasegurarse de que el informe de sus resultados cumpla con losrequisitos de calidad; deberia permitir a los investigadoresdeterminar rapidamente si toda la informacion relevante estaincluida en su manuscrito. Por supuesto, es posible cumplir contodos los factores en la lista de verificacion a pesar de haberrealizado un mal estudio y/o haber informado mal de un buenestudio, mientras que algunos elementos de la lista de chequeopueden no ser aplicables incluso para investigacionesrigurosamente realizadas. No obstante, la consideracion ydiscusion de los factores identificados en la lista de chequeodeberia mejorar la comunicacion de los resultados de lainvestigacion relacionada con el ejercicio y la nutricion, en elfuturo inmediato, y tiene el potencial de mejorar el diseno y larealizacion de ensayos a largo plazo.

Skeletal muscle generates superoxide during contractions which is rapidly converted to H2O2. This molecule has been proposed to activate signalling pathways and transcription factors that regulate key adaptive responses to exercise but the concentration of H2O2 required to oxidise and activate key signalling proteins in vitro is much higher than the intracellular concentration in muscle fibers following exercise. We hypothesised that Peroxiredoxins (Prx), which reacts with H2O2 at the low intracellular concentrations found in muscle, would be rapidly oxidised in contracting muscle and hence potentially transmit oxidising equivalents to downstream signalling proteins as a method for their oxidation and activation. The aim of this study was to characterise the effects of muscle contractile activity on the oxidation of Prx1, 2 and 3 and determine if these were affected by aging. Prx1, 2 and 3 were all rapidly and reversibly oxidised following treatment with low micromolar concentrations of H2O2 in C2C12 myotubes and also in isolated mature flexor digitalis brevis fibers from adult mice following a protocol of repeated isometric contractions. Significant oxidation of Prx2 was seen within 1 min (i.e. after 12 contractions), whereas significant oxidation was seen after 2 min for Prx1 and 3. In muscle fibers from old mice, Prx2 oxidation was significantly attenuated following contractile activity. Thus we show for the first time that Prx are rapidly and reversibly oxidised in response to contractile activity in skeletal muscle and hypothesise that these proteins act as effectors of muscle redox signalling pathways which are key to adaptations to exercise that are attenuated during aging., Graphical abstract Image 1, Highlights • Hydrogen peroxide is generated by skeletal muscle during contractions. • Peroxiredoxins (Prx) react with H2O2 at the physiological levels generated during contractions. • Prx 1–3 are all oxidised by H2O2 and contractile activity in muscle fibers. • Prx2 oxidation during contractions is attenuated in muscle fibers from old mice. • Prx may act as effectors in activation of redox-regulated adaptations to contractile activity in muscle.

To audit the current provision of performance nutrition services provided to male adolescent players within academies from the English soccer leagues. Practitioners from all 89 academies (status categorised as one-four according to the Elite Player Performance Plan, EPPP) completed an online survey to audit: a) job role/professional accreditation status of persons delivering nutrition support, b) activities inherent to service provision, c) topics of education, d) on-site food, fluid and supplement provision and e) nutritional related data collected for objective monitoring. More full-time accredited nutritionists are employed within category one (14/26) versus category two (0/18), three (1/41) and four (0/4). Respondents from category one clubs report more hours of monthly service delivery (62 ± 57 h) than category two (12 ± 9 h), three (14 ± 26 h) and four (12 ± 14 h), inclusive of one-to-one player support and stakeholder education programmes. Category one practitioners reported a greater prevalence of on-site food, fluid and supplement provision on training and match days. Across all categories, players from the professional development phase receive more frequent support than players from the youth development phase, despite the latter corresponding to the most rapid phase of growth and maturation. We report distinct differences in the extent of service provision provided between categories. Additionally, players from all categories receive nutrition support from non-specialist staff. Data demonstrate that performance nutrition appears an under-resourced component of academy sport science and medicine programmes in England, despite being an integral component of player development.

Golf is a sport played around the globe, with an estimated 42.6 million people playing within the United Kingdom and United States of America alone. To date, there is limited data on the energy expenditure of golf. The present study assessed the activity energy expenditure (AEE) of 16 high-standard (handicap under 5) golfers who completed three rounds of competitive golf either carrying the golf bag (BC), using a manual push trolley (MT) or an electric trolley (ET) (Stewart Golf, Gloucester, UK). Prior to each round, participants were fitted with an Actiheart® accelerometer (Camntech, Fenstanton, UK) to estimate AEE, whilst ratings of perceived exertion (RPE) and enjoyment were collected following each round. Data were analysed using a one-way repeated measures ANOVA, with Hedges

Rugby is characterized by frequent high-intensity collisions, resulting in muscle soreness. Players consequently seek strategies to reduce soreness and accelerate recovery, with an emerging method being cannabidiol (CBD), despite anti-doping risks. The prevalence and rationale for CBD use in rugby has not been explored; therefore, we recruited professional male players to complete a survey on CBD. Goodness of fit chi-square (χ2) was used to assess CBD use between codes and player position. Effects of age on use were determined using χ2 tests of independence. Twenty-five teams provided 517 player responses. While the majority of players had never used CBD (p V = 0.24), 26% had either used it (18%) or were still using it (8%). Significantly more CBD use was observed in rugby union compared with rugby league (p = .004, V = 0.13), but player position was not a factor (p = .760, V = 0.013). CBD use increased with players’ age (p V = 0.28), with mean use reaching 41% in the players aged 28 years and older category (p

This investigation sought to determine whether post-exercise cold water immersion and low glycogen availability, separately and in combination, would preferentially activate either the Exon 1a or Exon 1b Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) promoter. Through a reanalysis of sample design, we identified that the systemic cold-induced augmentation of total PGC-1α gene expression observed previously (Allan et al. in J Appl Physiol 123(2):451–459, 2017) was largely a result of increased expression from the alternative promoter (Exon 1b), rather than canonical promoter (Exon 1a). Low glycogen availability in combination with local cooling of the muscle (Allan et al. in Physiol Rep 7(11):e14082, 2019) demonstrated that PGC-1α alternative promoter (Exon 1b) expression continued to rise at 3 h post-exercise in all conditions; whilst, expression from the canonical promoter (Exon 1a) decreased between the same time points (post-exercise–3 h post-exercise). Importantly, this increase in PGC-1α Exon 1b expression was reduced compared to the response of low glycogen or cold water immersion alone, suggesting that the combination of prior low glycogen and CWI post-exercise impaired the response in gene expression versus these conditions individually. Data herein emphasise the influence of post-exercise cooling and low glycogen availability on Exon-specific control of total PGC-1 α gene expression and highlight the need for future research to assess Exon-specific regulation of PGC-1α.

The goal of professional soccer academies is to develop players who can progress and represent their first team or that can be sold for financial gain. As an academy player transitions through the academy pathway (i.e. from under, U9 to U23), they undergo distinct phases of growth and maturation that result in anatomical (e.g. an increase in stature and body mass), physiological (e.g. an increase in growth hormone, insulin-like growth factor 1, testosterone and thyroid hormones) and metabolic changes (e.g. increased glycolytic capabilities). The collective result of such changes are likely to influence such daily energy requirements. However, unlike professional adult players, the body composition, physical loading patterns and associated daily energy expenditure have not yet been quantified in academy soccer players. A detailed understanding of such parameters is fundamental in order to promote growth and maturation whilst also maximising each players physical and technical development. With this in mind, the aim of this thesis was to determine the energy requirements of male academy soccer players from the English Premier League of different chronological and biological ages. The aim of Study 1 (Chapter 4) was to assess body composition and resting metabolic rate in a cohort of academy soccer players. In a cross-sectional design, ninety-nine males from a Category One English Premier League academy (U12-U23 age-groups) underwent assessments of body composition (dual-energy X-ray absorptiometry, DXA) and resting metabolic rate (indirect calorimetry). Fat-free mass increased between the U12 (31.6 ± 4.2 kg) and U16 (56.3 ± 5.3 kg) age-groups after which no further increases occurred. Resting metabolic rate in the U12 (1655 ± 195 kcalday-1), U13 (1720 ± 205 kcalday-1) and U14 (1846 ± 218 kcalday-1) age-groups was significantly lower than the U15 (1957 ± 128 kcalday-1), U16 (2042 ± 155 kcalday-1), U18 (1875 ± 180 kcalday-1) and U23 (1941 ± 197 kcalday-1) age-groups. These data provide the first report of differences in body composition and resting metabolic rate in academy soccer players (as assessed via DXA and indirect calorimetry, respectively) and demonstrate that the growth and maturation occurring between U12-U16 significantly increases resting energy requirements. Having quantified body composition and resting metabolic rate in Study 1 (Chapter 4), the aim of Study 2 (Chapter 5) was to determine the typical weekly training and match loading patterns of academy soccer players. Over the course of an entire competitive season, weekly training and match load was quantified using global positioning system technology in 76 soccer players from a Category One English Premier League academy (U12-U18 age-groups). Weekly training and match volume (i.e. duration and total distance) was similar in the U12 (329 ± 29 min; 19.9 ± 2.2 km), U13 (323 ± 29 min; 20.0 ± 2.0 km) and U14 (339 ± 25 min; 21.7 ± 2.0 km) age-groups, but was lower than the U15 (421 ± 15 min; 26.2 ± 2.1 km), U16 (427 ± 20 min; 25.9 ± 2.5 km) and U18 (398 ± 30 min; 26.1 ± 2.6 km) age-groups. Weekly high-speed running and sprint distance (i.e. intensity) were comparable in the U12 (220 ± 95 m and 6 ± 9 m respectively), U13 (331 ± 212 m and 6 ± 27 m) and U14 (448 ± 193 m and 21 ± 29 m) age-groups was similar, but less than the U15 (657 ± 242 m and 49 ± 98 m), U16 (749 ± 152 m and 95 ± 55 m) and U18 (979 ± 254 m and 123 ± 56 m) age-groups. These data provide the first 4 report to objectively assess accumulative training and match loads in academy soccer players and demonstrate that the absolute loads are progressive in nature throughout the academy pathway. Given the progressive changes in body composition (Study 1, Chapter 4), resting metabolic rate (Study 1, Chapter 4) and physical loading patterns (Study 2, Chapter 5), the aim of Study 3 (Chapter 6) was to quantify the total daily energy expenditure of academy soccer players with different chronological and biological ages. Energy expenditure (doubly labelled water) and energy intake (remote food photographic method) was assessed over a 14-day in-season period in 24 soccer players from a Category One English Premier League academy (U12/13, n=8; U15, n=8; U18, n=8). U18 players presented with greater total energy expenditure (3586 ± 487 kcalday-1) than both the U15 (3029 ± 262 kcalday-1) and U12/13 players (2859 ± 265 kcalday-1), though no differences were evident between the U12/13 and U15 age-groups. Within age-groups, no differences were apparent between energy intake and total energy expenditure, whilst U18 players (3180 ± 279 kcalday-1) reported a higher energy intake than both the U15 (2821 ± 338 kcalday-1) and U12/13 (2659 ± 187 kcalday-1) players. In some individuals (evident in all age-groups) total energy expenditure was greater than that previously observed in adult English Premier League soccer players (3566 ± 585 kcalday-1). In summary, the data presented in this thesis provides the first report to simultaneously quantify body composition, resting metabolic rate, physical loading patterns and total daily energy expenditure of academy soccer players. Importantly, these data demonstrate that players’ absolute daily energy expenditure progressively increase as they become more biologically mature, likely a reflection of increased fat-free mass and physical loading patterns. From a practical perspective, these data will assist in developing population specific sport nutrition guidelines.

In the elderly, low protein intake exacerbates the effects of sarcopenia and anabolic resistance. Protein supplementation to maximise muscle protein synthesis, may be an effective intervention. Aim: To determine the effects of a low/high dose of protein, ingested immediately post-exercise, during resistance training in novice elderly males. Method: 24 elderly (70.5±5.1, years) males were recruited (body mass: 92.4±14.9 kg; fat free mass: 61.4±7.6 kg). After exclusion criteria, 18 males participated. Participants continued their normal dietary intake and were allocated into two matched groups, then randomly assigned to either a 20 g or 40 g dose intervention. Following determination of 1 repetition maximum (1RM), participants completed 10 x 3d

The COVID-19 pandemic in 2020 has resulted in widespread training disruption in many sports. Some athletes have access to facilities and equipment, while others have limited or no access, severely limiting their training practices. A primary concern is that the maintenance of key physical qualities (e. g. strength, power, high-speed running ability, acceleration, deceleration and change of direction), game-specific contact skills (e. g. tackling) and decision-making ability, are challenged, impacting performance and injury risk on resumption of training and competition. In extended periods of reduced training, without targeted intervention, changes in body composition and function can be profound. However, there are strategies that can dramatically mitigate potential losses, including resistance training to failure with lighter loads, plyometric training, exposure to high-speed running to ensure appropriate hamstring conditioning, and nutritional intervention. Athletes may require psychological support given the challenges associated with isolation and a change in regular training routine. While training restrictions may result in a decrease in some physical and psychological qualities, athletes can return in a positive state following an enforced period of rest and recovery. On return to training, the focus should be on progression of all aspects of training, taking into account the status of individual athletes.

For the first time we aimed to: (1) assess fat-free mass (FFM) and RMR in youth soccer players, (2) compare measured RMR to estimated RMR using previously published prediction equations, and (3) develop a novel population-specific prediction equation. In a cross-sectional design, 99 males from a Premier League academy underwent assessments of body composition (DXA) and RMR (indirect-calorimetry). Measured RMR was compared to estimated values from five prediction equations. A novel RMR prediction equation was developed using stepwise multiple regression. FFM increased (P0.05). RMR in the U12s (1655±195 kcal.day−1), U13s (1720±205 kcal.day−1) and U14s (1846±218kcal.day−1) was significantly lower than the U15s (1957±128 kcal.day−1), U16s (2042±155 kcal.day−1), U18s (1875±180 kcal.day−1) and U23s (1941±197 kcal.day−1) squads (P>0.05). FFM was the single best predictor of RMR (r2=0.43; P

In mammals, trait variation is often reported to be greater among males than females. However, to date, mainly only morphological traits have been studied. Energy expenditure represents the metabolic costs of multiple physical, physiological, and behavioral traits. Energy expenditure could exhibit particularly high greater male variation through a cumulative effect if those traits mostly exhibit greater male variation, or a lack of greater male variation if many of them do not. Sex differences in energy expenditure variation have been little explored. We analyzed a large database on energy expenditure in adult humans (1494 males and 3108 females) to investigate whether humans have evolved sex differences in the degree of interindividual variation in energy expenditure. We found that, even when statistically comparing males and females of the same age, height, and body composition, there is much more variation in total, activity, and basal energy expenditure among males. However, with aging, variation in total energy expenditure decreases, and because this happens more rapidly in males, the magnitude of greater male variation, though still large, is attenuated in older age groups. Considerably greater male variation in both total and activity energy expenditure could be explained by greater male variation in levels of daily activity. The considerably greater male variation in basal energy expenditure is remarkable and may be explained, at least in part, by greater male variation in the size of energy-demanding organs. If energy expenditure is a trait that is of indirect interest to females when choosing a sexual partner, this would suggest that energy expenditure is under sexual selection. However, we present a novel energetics model demonstrating that it is also possible that females have been under stabilizing selection pressure for an intermediate basal energy expenditure to maximize energy available for reproduction. (C) 2022 The Author(s). Published by Elsevier Ltd.

The term “food first” has been widely accepted as the preferred strategy within sport nutrition, although there is no agreed definition of this and often limited consideration of the implications. We propose that food first should mean “where practically possible, nutrient provision should come from whole foods and drinks rather than from isolated food components or dietary supplements.” There are many reasons to commend a food first strategy, including the risk of supplement contamination resulting in anti-doping violations. However, a few supplements can enhance health and/or performance, and therefore a food only approach could be inappropriate. We propose six reasons why a food only approach may not always be optimal for athletes: (a) some nutrients are difficult to obtain in sufficient quantities in the diet, or may require excessive energy intake and/or consumption of other nutrients; (b) some nutrients are abundant only in foods athletes do not eat/like; (c) the nutrient content of some foods with established ergogenic benefits is highly variable; (d) concentrated doses of some nutrients are required to correct deficiencies and/or promote immune tolerance; (e) some foods may be difficult to consume immediately before, during or immediately after exercise; and (f) tested supplements could help where there are concerns about food hygiene or contamination. In these situations, it is acceptable for the athlete to consider sports supplements providing that a comprehensive risk minimization strategy is implemented. As a consequence, it is important to stress that the correct terminology should be “food first but not always food only.”

Publisher Copyright: © 2021 The Authors Understanding the impacts of activity on energy balance is crucial. Increasing levels of activity may bring diminishing returns in energy expenditure because of compensatory responses in non-activity energy expenditures.1–3 This suggestion has profound implications for both the evolution of metabolism and human health. It implies that a long-term increase in activity does not directly translate into an increase in total energy expenditure (TEE) because other components of TEE may decrease in response—energy compensation. We used the largest dataset compiled on adult TEE and basal energy expenditure (BEE) (n = 1,754) of people living normal lives to find that energy compensation by a typical human averages 28% due to reduced BEE; this suggests that only 72% of the extra calories we burn from additional activity translates into extra calories burned that day. Moreover, the degree of energy compensation varied considerably between people of different body compositions. This association between compensation and adiposity could be due to among-individual differences in compensation: people who compensate more may be more likely to accumulate body fat. Alternatively, the process might occur within individuals: as we get fatter, our body might compensate more strongly for the calories burned during activity, making losing fat progressively more difficult. Determining the causality of the relationship between energy compensation and adiposity will be key to improving public health strategies regarding obesity.

Reactive oxygen species (ROS) are recognized as important signaling molecules in healthy skeletal muscle. Redox sensitive proteins can respond to intracellular changes in ROS by oxidation of reactive thiol groups on cysteine (Cys) residues. Exercise is known to induce the generation of superoxide and nitric oxide, resulting in the activation of several adaptive signaling pathways; however, it has been suggested that aging attenuates these redox-regulated adaptations to acute exercise. In the present study, we used redox proteomics to study the vastus lateralis muscles of Adult (n = 6 male, 6 female; 18–30 yrs) and Old (n = 6 male, 6 female; 64–79 yrs) adults. Participants completed a bout of high intensity cycling exercise consisting of five sets of 2-min intervals performed at 80% maximal aerobic power output (PPO), with 2 min recovery cycling at 40% PPO between sets. Muscle biopsies were collected prior to exercise, and immediately following the first, second, and fifth high intensity interval. Global proteomic analysis indicated differences in abundance of a number of individual proteins between skeletal muscles of Adult and Old subjects at rest with a significant exacerbation of these differences induced by the acute exercise. In particular, we observed an exercise-induced decrease in abundance of mitochondrial proteins in muscles from older subjects only. Redox proteome analysis revealed cysteines from five cytosolic proteins in older subjects with lower oxidation (i.e. greater reduction) than was seen in muscle from the young adults at rest. Redox homeostasis was well maintained in Adult subjects following exercise, but there was significant increase in oxidation of multiple mitochondrial and cytosolic protein cysteines in Old subjects. We also observed that oxidation of peroxiredoxin 3 occurred following exercise in both Adult and Old groups, supporting the possibility that this is a key effector protein for mitochondrial redox signaling. Thus, we show, for the first time that exercise reveals a lack of resilience in muscle of older human participants, that is apparent as a loss of mitochondrial proteins and oxidation of multiple protein cysteines that are not seen in younger subjects. The precise consequences of this redox disruption are unclear, but this likely play a role in the attenuation of multiple adaptations to exercise that are classically seen with aging. Such changes were only seen following the acute stress of exercise., highlighting the need to consider not only basal differences seen during aging but also the difference following physiological challenge.

Few data are available that describe how probiotics influence systemic metabolism during endurance exercise. Metabolomic profiling of endurance athletes will elucidate mechanisms by which probiotics may confer benefits to the athlete. In this study, twenty-four runners (20 male, 4 female) were block randomised into two groups using a double-blind matched-pairs design according to their most recent Marathon performance. Runners were assigned to 28-days of supplementation with a multi-strain probiotic (PRO) or a placebo (PLB). Following 28-days of supplementation, runners performed a competitive track Marathon race. Venous blood samples and muscle biopsies (vastus lateralis) were collected on the morning of the race and immediately post-race. Samples were subsequently analysed by untargeted 1H-NMR metabolomics. Principal component analysis (PCA) identified a greater difference in the post-Marathon serum metabolome in the PLB group vs. PRO. Univariate tests identified 17 non-overlapped metabolites in PLB, whereas only seven were identified in PRO. By building a PLS-DA model of two components, we revealed combinations of metabolites able to discriminate between PLB and PRO post-Marathon. PCA of muscle biopsies demonstrated no discernible difference post-Marathon between treatment groups. In conclusion, 28-days of probiotic supplementation alters the metabolic perturbations induced by a Marathon. Such findings may be related to maintaining the integrity of the gut during endurance exercise.

Understanding the total energy expenditure (TEE) for competition and training in sport are vital to ensure suitable nutritional strategies. This study assessed TEE of a world class male and female tennis player during competition at the highest level. Participants: Career high ranking, Female: Women's Tennis Association (WTA) top 10; Male: Association of Tennis Professionals (ATP) top 15. Methods: Doubly labelled water assessed TEE during a 17-day period analysed by day 1-7 (P1) and 7-17 (P2) which included a WTA/ATP tournament and culminated at the Wimbledon Championships. Daily training and match loads were assessed using a 10-point Borg scale multiplied by time. Match data were provided by video analysis and player tracking technology. Results: The TEE during P1 for the female player was 3383 kcal⋅day-1 (63.5 kcal⋅kg-1) FFM with 362 points played over 241 min in three matches covering a distance of 2569 m, with an additional 875 min training. During P2, TEE was 3824 kcal⋅day-1 (71.7 kcal⋅kg-1) FFM with 706 points played over 519 min during five matches, covering a distance of 7357 m with an additional 795 min training. The TEE during P1 for the male player was 3712 kcal⋅day-1 (56.3 kcal⋅kg-1) FFM with 133 points played over 88 mins during one match covering 1125 m, with an additional 795 mins training. During P2, TEE was 5520 kcal⋅day-1 (83.7 kcal⋅kg-1) FFM with 891 points played over 734 min during five matches, covering 10043 m, with an additional 350 min training. Conclusion: This novel data positions elite tennis, played at the highest level, as a highly energetic demanding sport, highlighting that nutritional strategies should ensure sufficient energy availability during competition schedules.

Cannabis is widely used for both recreational and medicinal purposes on a global scale. There is accumulating interest in the use of cannabis and its constituents for athletic recovery, and in some instances, performance. Amidst speculation of potential beneficial applications, the effects of cannabis and its two most abundant constituents, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), remain largely un-investigated. The purpose of this review is to critically evaluate the literature describing the effects of whole cannabis, THC, and CBD, on athletic performance and recovery. While investigations of whole cannabis and THC have generally shown either null or detrimental effects on exercise performance in strength and aerobic-type activities, studies of sufficient rigor and validity to conclusively declare ergogenic or ergolytic potential in athletes are lacking. The ability of cannabis and THC to perturb cardiovascular homeostasis warrants further investigation regarding mechanisms by which performance may be affected across different exercise modalities and energetic demands. In contrast to cannabis and THC, CBD has largely been scrutinized for its potential to aid in recovery. The beneficial effects of CBD on sleep quality, pain, and mild traumatic brain injury may be of particular interest to certain athletes. However, research in each of these respective areas has yet to be thoroughly investigated in athletic populations. Elucidating the effects of whole cannabis, THC, and CBD is pertinent for both researchers and practitioners given the widespread use of these products, and their potential to interact with athletes’ performance and recovery.

Maintaining muscle mass and function during rehabilitation from anterior cruciate ligament injury is complicated by the challenge of accurately prescribing daily energy intakes aligned to energy expenditure. Accordingly, we present a 38-week case study characterizing whole body and regional rates of muscle atrophy and hypertrophy (as inferred by assessments of fat-free mass from dual-energy X-ray absorptiometry) in a professional male soccer player from the English Premier League. In addition, in Week 6, we also quantified energy intake (via the remote food photographic method) and energy expenditure using the doubly labeled water method. Mean daily energy intake (CHO: 1.9–3.2, protein: 1.7–3.3, and fat: 1.4–2.7 g/kg) and energy expenditure were 2,765 ± 474 and 3,178 kcal/day, respectively. In accordance with an apparent energy deficit, total body mass decreased by 1.9 kg during Weeks 1–6 where fat-free mass loss in the injured and noninjured limb was 0.9 and 0.6 kg, respectively, yet, trunk fat-free mass increased by 0.7 kg. In Weeks 7–28, the athlete was advised to increase daily CHO intake (4–6 g/kg) to facilitate an increased daily energy intake. Throughout this period, total body mass increased by 3.6 kg (attributable to a 2.9 and 0.7 kg increase in fat free and fat mass, respectively). Our data suggest it may be advantageous to avoid excessive reductions in energy intake during the initial 6–8 weeks post anterior cruciate ligament surgery so as to limit muscle atrophy.

This study aimed to explore how social media is being used by sports nutritionists as part of service provision, as well as practitioners’ experiences and opinions of its use in practice. An exploratory sequential mixed methods approach was used during this research. Forty-four sports nutritionists completed an online survey detailing their personal and professional social media use. Semi-structured follow-up interviews were conducted with 16 participants who volunteered to do so. Survey responses were collated and reported as descriptive statistics. Interviews were thematically analysed. \ud Social media was used by 89% of sports nutritionists to support practice, of which 97% perceived its use to be beneficial. Platforms were used to deliver information and resources, and support athletes online via pages, groups and 1-2-1 messaging. Social media facilitated improved communication between the practitioner and the athlete, as well as facilitating mobile and visual learning. Lack of digital intervention training and time were reported as challenges to social media use in practice. \ud Sports nutritionists have embraced social media as an extension of service provision. Professional education should now consider supporting nutritionists’ in developing digital professionalism.

Clarke, JS, Highton, J, Close, GL, and Twist, C. Carbohydrate and caffeine improves high-intensity running of elite rugby league interchange players during simulated match play. J Strength Cond Res 33(5): 1320-1327, 2019-The study examined the effects of carbohydrate and caffeine ingestion on simulated rugby league interchange performance. Eight male elite rugby league forwards completed 2 trials of a rugby league simulation protocol for interchange players 7 days apart in a randomized crossover design, ingesting either carbohydrate (CHO; 40 g·h) or carbohydrate and caffeine (CHO-C) (40 g·h + 3 mg·kg) drink. Movement characteristics, heart rate, ratings of perceived exertion (RPE), and countermovement jump (CMJ) height were measured during the protocol. CHO-C resulted in likely to very likely higher mean running speeds (effect size [ES] 0.43-0.75), distance in high-intensity running (ES 0.41-0.64), and mean sprint speeds (ES 0.39-1.04) compared with CHO. Heart rate was possibly to very likely higher (ES 0.32-0.74), and RPE was likely to very likely lower (ES -0.53 to 0.86) with CHO-C. There was a likely trivial to possibly higher CMJ in CHO-C compared with CHO (ES 0.07-0.25). The coingestion of carbohydrate with caffeine has an ergogenic effect to reduce the sense of effort and increase high-intensity running capability that might be used to enhance interchange running performance in elite rugby league players.