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Carbohydrates are critical for high‐intensity exercise performance. However, the effects of carbohydrate supplementation on muscle metabolism and performance during short‐duration high‐intensity intermittent exercise remain inadequately explored. Our aim was to address this aspect in a randomized, counterbalanced, double‐blinded crossover design. Eleven moderately‐to‐well‐trained males performed high‐intensity intermittent cycling receiving carbohydrate (CHO, ~55 g/h) or placebo (PLA) fluid supplementation. Three exercise periods (EX1‐EX3) were completed comprising 10 × 45 s at ~105% Wmax interspersed with 135 s rest between bouts and ~20 min between periods. Repeated sprint ability (5 × 6 s sprints with 24 s recovery) was assessed at baseline and after each period. Thigh muscle biopsies were obtained at baseline and before and after EX3 to determine whole‐muscle and fiber‐type‐specific glycogen depletion. No differences were found in muscle glycogen degradation at the whole‐muscle (p = 0.683) or fiber‐type‐specific level (p = 0.763–0.854) with similar post‐exercise whole‐muscle glycogen concentrations (146 ± 20 and 122 ± 15 mmol·kg−1 dw in CHO and PLA, respectively). Repeated sprint ability declined by ~9% after EX3 with no between‐condition differences (p = 0.971) and no overall differences in ratings of perceived exertion (p = 0.550). This was despite distinctions in blood glucose concentrations throughout exercise, reaching post‐exercise levels of 5.3 ± 0.2 and 4.1 ± 0.2 mmol·L−1 (p < 0.001) in CHO and PLA, respectively, accompanied by fivefold higher plasma insulin levels in CHO (p < 0.001). In conclusion, we observed no effects of carbohydrate ingestion on net muscle glycogen breakdown or sprint performance during short‐duration high‐intensity intermittent exercise despite elevated blood glucose and insulin levels. These results therefore question the efficacy of carbohydrate supplementation strategies in high‐intensity intermittent sports. [ABSTRACT FROM AUTHOR]

Ice hockey is an intense team sport characterized by repeated bursts of fast‐paced skating, rapid changes in speed and direction and frequent physical encounters. These are performed in on‐ice shifts of ~30–80 s interspersed with longer sequences of passive recovery, resulting in about 15–25 min on‐ice time per player. Nearly 50% of the distance is covered at high‐intensity skating speeds and with an accentuated intense activity pattern in forwards compared to defensemen. During ice hockey match‐play, both aerobic and anaerobic energy systems are significantly challenged, with the heart rate increasing toward maximum levels during each shift, and with great reliance on both glycolytic and phosphagen ATP provision. The high‐intensity activity pattern favors muscle glycogen as fuel, leading to pronounced reductions despite the relatively brief playing time, including severe depletion of a substantial proportion of individual fast‐ and slow‐twitch fibers. Player‐tracking suggests that the ability to perform high‐intensity skating is compromised in the final stages of a game, which is supported by post‐game reductions in repeated‐sprint ability. Muscle glycogen degradation, in particular in individual fibers, as well as potential dehydration and hyperthermia, may be prime candidates implicated in exacerbated fatigue during the final stages of a game, whereas multiple factors likely interact to impair exercise tolerance during each shift. This includes pronounced PCr degradation, with potential inadequate resynthesis in a proportion of fast‐twitch fibers in situations of repeated intense actions. Finally, the recovery pattern is inadequately described, but seems less long‐lasting than in other team sports. [ABSTRACT FROM AUTHOR]

Despite the frequent occurrence of congested game fixtures in elite ice hockey, the postgame recovery pattern has not previously been investigated. The purpose of the present study was therefore to evaluate the acute decrements and subsequent recovery of skeletal muscle glycogen levels, muscle function and repeated‐sprint ability following ice hockey game‐play. Sixteen male players from the Danish U20 national team completed a training game with muscle biopsies obtained before, postgame and following ~38 h of recovery (day 2). On‐ice repeated‐sprint ability and muscle function (maximal voluntary isometric [MVIC] and electrically induced low‐ (20 Hz) and high‐frequency (50 Hz) knee‐extensor contractions) were assessed at the same time points, as well as ~20 h into recovery (day 1). Muscle glycogen decreased 31% (p < 0.001) postgame and had returned to pregame levels on day 2. MVIC dropped 11%, whereas 50 and 20 Hz torque dropped 21% and 29% postgame, respectively, inducing a 10% reduction in the 20/50 Hz torque ratio indicative of low‐frequency force depression (all p < 0.001). While MVIC torque returned to baseline on day 1, 20 and 50 Hz torque remained depressed by 9%–11% (p = 0.010–0.040), hence restoring the pre‐exercise 20/50 Hz ratio. Repeated‐sprint ability was only marginally reduced by 1% postgame (p = 0.041) and fully recovered on day 1. In conclusion, an elite youth ice hockey game induces substantial reductions in muscle glycogen content and muscle function, but only minor reductions in repeated‐sprint ability and with complete recovery of all parameters within 1–2 days postgame. [ABSTRACT FROM AUTHOR]

This study aimed at examining the dose-response of a recreational team handball (TH) exercise-based programme on cardiometabolic health and physical fitness in inactive middle-aged-to-elderly males without TH experience. Fifty-four inactive middle-aged-to-elderly men (67.5 ± 4.2 years; stature 168.8 ± 6.2 cm; body mass 78.4 ± 10.7 kg; fat mass 27.1 ± 5.3%; BMI 27.4 ± 2.9 kg/m2; VO2peak 27.3 ± 4.8 mL/min/kg) were randomised into three intervention groups performing 1 (TH1, n = 13), 2 (TH2, n = 15), or 3 (TH3, n = 12) 60-min weekly recreational TH-based training sessions, for 16 weeks, and a control group (CG, n = 14). A time x group interaction was observed for VO2peak, aerobic performance, fasting plasma insulin and body and fat mass (p ≤ 0.043) with TH3 showing the greatest overall effects. Post-intervention differences were observed in aerobic performance (TH3>CG, TH1 and TH2; TH2>CG), body mass (TH3>CG and TH1), fat mass (TH3>CG), VO2peak (TH3>CG) and plasma insulin (TH3>CG) (p ≤ 0.040). In conclusion, recreational TH performed for 60-min thrice and twice per week results in improved aerobic performance for middle-aged-to-elderly men. Moreover, it was observed that three weekly sessions were more effective in providing overall cardiometabolic benefits compared to training with a lower weekly frequency. ClinicalTrials.gov ID: NCT05295511. Trial registration: ClinicalTrials.gov identifier: NCT05295511. Highlights: We observed high intensities and fun levels during recreational TH, organised as formal and small-sided games, for middle-aged-to-elderly men during a 16-week period, independently of the number of weekly training sessions. Marked positive effects on aerobic performance and cardiometabolic health were observed in the intervention group that performed 3 weekly sessions. The study results indicate that recreational TH training with low frequency and volume results in some beneficial effects on cardiometabolic fitness and health for middle-aged-to-elderly men, but future studies with more participants or longer intervention periods are warranted to explore this possibility. [ABSTRACT FROM AUTHOR]

Background: We aimed to investigate the popularity of the "11 for Health program for Europe" for 10–12‐year‐old Faroese children and the effects on well‐being and health knowledge. Methods: We applied a cluster‐randomized controlled trial, including a total of 19 school clusters, randomized into intervention schools (IG, n = 12) and control schools (CG, n = 7). A total of 261 children (137 boys and 124 girls) participated. IG completed the 11‐week program, consisting of 2 × 45 min weekly sessions with football drills, small‐sided games, and health education. CG continued their regular education. Pre‐ and post‐intervention, the participants completed a shortened version of the multidimensional well‐being questionnaire KIDSCREEN‐27 and a 34‐item multiple‐choice health knowledge questionnaire. Results: Between‐group differences (p < 0.05) were observed in change scores for physical well‐being and overall peers and social support in favor of IG compared with CG, as well as for physical well‐being in IG girls compared with CG girls. Between‐group differences in change score for overall health knowledge (11.8%, p < 0.001, ES: 0.82) were observed in favor of IG, as well as for playing football (8.9%, p = 0.039, ES: 0.24), be active (8.1%, p = 0.017, ES: 0.32), control your weight (18.5%, p < 0.001, ES: 0.52), wash your hands (19.5%, p < 0.001, ES: 0.59), eat a balanced diet (19.3%, p < 0.001, ES: 0.64), get fit (12.1%, p = 0.007, ES: 0.34), and think positive (5.5%, p = 0.039, ES: 0.22). The program was reported as enjoyable with equal moderate‐to‐high scores for girls (3.68 ± 1.23; ±SD) and boys (3.84 ± 1.17) on a 1–5 Likert Scale. Conclusion: The "11 for Health program for Europe" improved physical well‐being, peers, and social support and broad‐spectrum health knowledge in 10–12‐year‐old Faroese schoolchildren and was rated popular. [ABSTRACT FROM AUTHOR]

Glycogen particles are situated in key areas of the muscle cell in the vicinity of the main energy‐consumption sites and may be utilised heterogeneously dependent on the nature of the metabolic demands. The present study aimed to investigate the time course of fibre type‐specific utilisation of muscle glycogen in three distinct subcellular fractions (intermyofibrillar, IMF; intramyofibrillar, Intra; and subsarcolemmal, SS) during repeated high‐intensity intermittent exercise. Eighteen moderately to well‐trained male participants performed three periods of 10 × 45 s cycling at ∼105% watt max (EX1–EX3) coupled with 5 × 6 s maximal sprints at baseline and after each period. Muscle biopsies were sampled at baseline and after EX1 and EX3. A higher glycogen breakdown rate in type 2 compared to type 1 fibres was found during EX1 for the Intra (−72 vs. −45%) and IMF (−59 vs. −35%) glycogen fractions (P < 0.001) but with no differences for SS glycogen (−52 vs. −40%). In contrast, no fibre type differences were observed during EX2–EX3, where the utilisation of Intra and IMF glycogen in type 2 fibres was reduced, resulting in depletion of all three subcellular fractions to very low levels post‐exercise within both fibre types. Importantly, large heterogeneity in single‐fibre glycogen utilisation was present with an early depletion of especially Intra glycogen in individual type 2 fibres. In conclusion, there is a clear fibre type‐ and localisation‐specific glycogen utilisation during high‐intensity intermittent exercise, which varies with time course of exercise and is characterised by exacerbated pool‐specific glycogen depletion at the single‐fibre level. Key points: Muscle glycogen is the major fuel during high‐intensity exercise and is stored in distinct subcellular areas of the muscle cell in close vicinity to the main energy consumption sites.In the present study quantitative electron microscopy imaging was used to investigate the utilisation pattern of three distinct subcellular muscle glycogen fractions during repeated high‐intensity intermittent exercise.It is shown that the utilisation differs dependent on fibre type, subcellular localisation and time course of exercise and with large single‐fibre heterogeneity.These findings expand on our understanding of subcellular muscle glycogen metabolism during exercise and may help us explain how reductions in muscle glycogen can attenuate muscle function even at only moderately lowered whole‐muscle glycogen concentrations. [ABSTRACT FROM AUTHOR]

Angiotensin‐converting enzyme (ACE) activity may be one determinant of adaptability to exercise training, but well‐controlled studies in humans without confounding conditions are lacking. Thus, the purpose of the present study was to investigate whether ACE inhibition affects cardiovascular adaptations to exercise training in healthy humans. Healthy participants of both genders (40 ± 7 years) completed a randomized, double‐blind, placebo‐controlled trial. Eight weeks of exercise training combined with placebo (PLA, n = 25) or ACE inhibitor (ACEi, n = 23) treatment was carried out. Before and after the intervention, cardiovascular characteristics were investigated. Mean arterial blood pressure was reduced (p < 0.001) by −5.5 [−8.4; −2.6] mmHg in ACEi, whereas the 0.7 [−2.0; 3.5] mmHg fluctuation in PLA was non‐significant. Maximal oxygen uptake increased (p < 0.001) irrespective of ACE inhibitor treatment by 13 [8; 17] % in ACEi and 13 [9; 17] % in PLA. In addition, skeletal muscle endurance increased (p < 0.001) to a similar extent in both groups, with magnitudes of 82 [55; 113] % in ACEi and 74 [48; 105] % in PLA. In contrast, left atrial volume decreased (p < 0.05) by −9 [−16; −2] % in ACEi, but increased (p < 0.01) by 14 [5; 23] % in PLA. Total hemoglobin mass was reduced (p < 0.01) by −3 [−6; −1] % in ACEi, while a non‐significant numeric increase of 2 [−0.4; 4] % existed in PLA. The lean mass remained constant in ACEi but increased (p < 0.001) by 3 [2; 4] % in PLA. In healthy middle‐aged adults, 8 weeks of high‐intensity exercise training increases maximal oxygen uptake and skeletal muscle endurance irrespective of ACE inhibitor treatment. However, ACE inhibitor treatment counteracts exercise training‐induced increases in lean mass and left atrial volume. ACE inhibitor treatment compromises total hemoglobin mass. [ABSTRACT FROM AUTHOR]

The present special issue of Scandinavian Journal of Medicine & Science in Sports focuses on performance, recovery, diet, and health in elite women's football. Beside this summary, an editorial, topic reviews, and original articles written by several of the most published authors in football research are presented. It is, for example, highlighted that there is a great gender inequality in football research in favor of men, especially within elite football populations. Therefore, the broad‐spectrum content of the special issue with focus on several performance areas in women's football, recovery strategies, nutrition, and psychological factors is highly warranted. Several of the topics examined and data presented are examined for the first on elite women's football, and therefore, we hope that this special issue will contribute to gender balance the research and emphasis on football in both genders. [ABSTRACT FROM AUTHOR]

We combined game activity analyses with skeletal muscle phenotypes and comprehensive physiological testing to elucidate factors of importance for physical performance in elite women's football. GPS‐data from an experimental game, sprint and endurance testing, and muscle tissue analysis of metabolic enzyme activity, protein expression and fiber type composition were completed for international top‐level women players (n = 20; age; 23 ± 4 yrs, height; 166 ± 10 cm, weight; 60 ± 8 kg; VO2max; 51 ± 6 ml/min/kg). Muscle monocarboxylate transporter 4 (MCT4) protein expression explained 46% of the variance in total game distance, while the ability to maintain high‐intensity running (HIR) during the final 15 min of the game correlated to myosin heavy chain 1 (MHCI) and Na+‐K+ ATPase β1, FXYD1 (phospholemman) and superoxide dismutase 2 (SOD2) protein expression (range: r = 0.51–0.71; all p < 0.05). Total HIR distance correlated with (MHCIIa) protein expression (r = 0.51; p < 0.05), while muscle Na+/H+ exchanger 1 (NHE1) protein explained 36% of the variance in game sprint distance (p < 0.05). Total game accelerations (actions >4 m/s2) correlated with platelet endothelial cell adhesion molecule (PECAM‐1) protein expression (r = 0.51; p < 0.05), while concentric knee flexor strength explained 42–62% of the variance in intense decelerations (>4 m/s2). In conclusion, for elite women players' game endurance performance and resistance to end‐game fatigue were affected by monocarboxylate transporter expression and myosin heavy chain profile. HIR was also correlated to ion transporter expression and muscle antioxidative capacity. Finally, the importance of functional strength and measures of muscle vascularization in relation to total game decelerations and accelerations, respectively, illustrates the complex physiological demands in elite women's football. [ABSTRACT FROM AUTHOR]

The present study examined skeletal muscle metabolism and changes in repeated sprint performance during match play for n = 20 competitive elite women outfield players. We obtained musculus vastus lateralis biopsies and blood samples before, after, and following intense periods in each half of a friendly match, along with 5 × 30‐meter sprint tests and movement pattern analyses (10‐Hz S5 Global Positioning System [GPS]). Muscle glycogen decreased by 39% and 42% after an intense period of the second half and after the match, respectively, compared to baseline (p < 0.05). Post‐match, 80% type I fibers and 69% type II fibers were almost empty or completely empty of glycogen. Muscle lactate was higher (p < 0.05) after the intense period of the first half and post‐match compared to baseline (14.3 ± 4.6 (±SEM) and 12.9 ± 5.7 vs. 6.4 ± 3.7 mmol/kg d.w.). Muscle phosphocreatine was reduced (p < 0.05) by 16% and 12%, respectively, after an intense period in the first and second half compared to baseline. Blood lactate and glucose increased during the match and peaked at 8.4 ± 2.0 and 7.9 ± 1.2 mmol/L, respectively. Mean 5 × 30 m sprint time declined by 3.2 ± 1.7 and 7.0 ± 2.1% after the first and second half, respectively, and 4.7 ± 1.6% (p < 0.05) after an intense period in the first half compared to baseline. In conclusion, match play in elite female football players resulted in marked glycogen depletion in both fiber types, which may explain fatigue at the end of a match. Repeated sprint ability was impaired after intense periods in the first half and after both halves, which may be associated with the observed muscle metabolite perturbations. [ABSTRACT FROM AUTHOR]

Women's football is an intermittent sport characterized by frequent intense actions throughout the match. The high number of matches with limited recovery time played across a long competitive season underlines the importance of nutritional strategies to meet these large physical demands. In order to maximize sport performance and maintain good health, energy intake must be optimal. However, a considerable proportion of female elite football players does not have sufficient energy intake to match the energy expenditure, resulting in low energy availability that might have detrimental physiologic consequences and impair performance. Carbohydrates appear to be the primary fuel covering the total energy supply during match‐play, and female elite football players should aim to consume sufficient carbohydrates to meet the requirements of their training program and to optimize the replenishment of muscle glycogen stores between training bouts and matches. However, several macro‐ and micronutrients are important for ensuring sufficient energy and nutrients for performance optimization and for overall health status in female elite football players. The inadequacy of macro‐and micronutrients in the diet of these athletes may impair performance and training adaptations, and increase the risk of health disorders, compromising the player's professional career. In this topical review, we present knowledge and relevant nutritional recommendations for elite female football players for the benefit of sports nutritionists, dietitians, sports scientists, healthcare specialists, and applied researchers. We focus on dietary intake and cover the most pertinent topics in sports nutrition for the relevant physical demands in female elite football players as follows: energy intake, macronutrient and micronutrient requirements and optimal composition of the everyday diet, nutritional and hydration strategies to optimize performance and recovery, potential ergogenic effects of authorized relevant supplements, and future research considerations. [ABSTRACT FROM AUTHOR]

The authors explore the evolution of football and speculate on the impact that the organizational and tactical changes may have on players' performance, mental, and physical health. Topics mentioned include an increase in the number of passes per minute at the FIFA World Cup finals between 1966 and 2010, limited time of players for recovery in the near future due to the congested schedules, and implementation of appropriate coaching education by football governing bodies and clubs.

The effects of football training on bone health were examined in 55‐ to 70‐year‐old sedentary women and men with prediabetes. Patients (n = 50) with prediabetes (age; 61 ± 9 years, BMI 29.7 ± 0.6 kg/m2, body fat content; 37 ± 1%, VO2max; 22.7 ± 0.8 mL/min/kg and mean arterial pressure; 104 ± 3 mm Hg) were randomized into a football training group (FTG; n = 27, 14 women) and a control group (CON; n = 23, 11 women). At baseline, 73% and 24% were diagnosed with femur osteopenia and osteoporosis, respectively. FTG performed football training twice weekly 30‐60‐minute sessions in 16 weeks, and both FTG and CON received professional dietary advice. Pre‐ and post‐intervention whole‐body and regional bone mineral content (BMC) and density (BMD) were determined with DXA‐scans, and venous blood samples were drawn and analyzed for plasma bone turnover markers. Change scores were greater (P < 0.05) in FTG compared to CON in leg BMD (0.023 ± 0.005 vs −0.004 ± 0.001 g/cm2) and in leg BMC (32 ± 8 vs −4 ± 6 g). Between‐group changes in favor of FTG (P < 0.05) also occurred in the femur neck BMD (3.2%) and femur shaft BMD (2.5%). Whole‐body BMC and BMD were unchanged in both groups during the intervention. In FTG, resting plasma osteocalcin, P1NP, and CTX‐1 rose (P < 0.05) by 23 ± 8, 52 ± 9 and 38 ± 7%, with greater change scores (P < 0.05) than in CON. Finally, P1NP (formation)/CTX‐1 (resorption) ratio increased (P < 0.05) in FTG (127 ± 15 vs 150 ± 11) from pre‐ to post‐intervention, with no change in CON (124 ± 12 and 123 ± 12). In conclusion, football training provides a powerful osteogenic stimulus and improves bone health in 55‐ to 70‐year‐old women and men diagnosed with prediabetes. [ABSTRACT FROM AUTHOR]

Key points The power-asymptote (critical power; CP) of the hyperbolic power-time relationship for high-intensity exercise defines a threshold between steady-state and non-steady-state exercise intensities and the curvature constant ( W′) indicates a fixed capacity for work >CP that is related to a loss of muscular efficiency., The present study reports novel evidence on the muscle metabolic underpinnings of CP and W′ during whole-body exercise and their relationships to muscle fibre type., We show that the W′ is not correlated with muscle fibre type distribution and that it represents an elevated energy contribution from both oxidative and glycolytic/glycogenolytic metabolism., We show that there is a positive correlation between CP and highly oxidative type I muscle fibres and that muscle metabolic steady-state is attainable CP., Our findings indicate a mechanistic link between the bioenergetic characteristics of muscle fibre types and the power-time relationship for high-intensity exercise., Abstract We hypothesized that: (1) the critical power (CP) will represent a boundary separating steady-state from non-steady-state muscle metabolic responses during whole-body exercise and (2) that the CP and the curvature constant ( W′) of the power-time relationship for high-intensity exercise will be correlated with type I and type IIx muscle fibre distributions, respectively. Four men and four women performed a 3 min all-out cycling test for the estimation of CP and constant work rate (CWR) tests slightly >CP until exhaustion ( Tlim), slightly CP Tlim isotime to test the first hypothesis. Eleven men performed 3 min all-out tests and donated muscle biopsies to test the second hypothesis. Below CP, muscle [PCr] [42.6 ± 7.1 vs. 49.4 ± 6.9 mmol (kg d.w.)−1], [La−] [34.8 ± 12.6 vs. 35.5 ± 13.2 mmol (kg d.w.)−1] and pH (7.11 ± 0.08 vs. 7.10 ± 0.11) remained stable between ∼12 and 24 min ( P > 0.05 for all), whereas these variables changed with time >CP such that they were greater [[La−] 95.6 ± 14.1 mmol (kg d.w.)−1] and lower [[PCr] 24.2 ± 3.9 mmol (kg d.w.)−1; pH 6.84 ± 0.06] ( P < 0.05) at Tlim (740 ± 186 s) than during the

A rise in extracellular potassium concentration in human skeletal muscle may play an important role in development of fatigue during intense exercise. The aim of the present study was to examine the effect of intense intermittent training on muscle interstitial potassium kinetics and its relationship to the density of Na+,K+-ATPase subunits and KATP channels, as well as exercise performance, in human skeletal muscle. Six male subjects performed intense one-legged knee-extensor training for 7 weeks. On separate days the trained leg (TL) and the control leg (CL) performed a 30 min exercise period of 30 W and an incremental test to exhaustion. At frequent intervals during the exercise periods interstitial potassium ([K+]I) was determined by microdialysis, femoral arterial and venous blood samples were drawn and thigh blood flow was measured. Time to fatigue for TL was 28% longer (P < 0.05) than for CL (10.6 ± 0.7 (mean 4- S.E.M.) versus 8.2 4- 0.7 min). The amounts of Na+,K+-ATPase α1 and α2 subunits were, respectively, 29.0 ± 8.4 and 15.1 ± 2.7% higher (P < 0.05) in TL than in CL, while the amounts of β1 subunits and ATP-dependent K+ (KATP) channels were the same. In CL [K+]I increased more rapidly and was higher (P < 0.05) throughout the 30 W exercise bout, as well at 60 and 70 W, compared to TL, whereas [K+]I was similar at the point of fatigue (9.9 ± 0.7 and 9.1 ± 0.5 mmol 1-1, respectively). During the 30 W exercise bouts and at 70 W during the incremental exercise femoral venous potassium concentration ([K+]v) was higher (P < 0.05) in CL than in TL, but identical at exhaustion (6.2 ± 0.2 mmol 1-1). Release of potassium to the blood was not different in the two legs. The... [ABSTRACT FROM AUTHOR]

While it is well‐established that a period of interval training performed at near maximal effort, such as speed endurance training (SET), enhances intense exercise performance in well‐trained individuals, less is known about its effect on cardiac morphology and function as well as blood volume. To investigate this, we subjected 12 Under‐20 Danish national team ice hockey players (age 18 ± 1 years, mean ± SD) to 4 weeks of SET, consisting of 6–10 × 20 s skating bouts at maximal effort interspersed by 2 min of recovery conducted three times weekly. This was followed by 4 weeks of regular training (follow‐up). We assessed resting cardiac function and dimensions using transthoracic echocardiography and quantified total blood volume with the carbon monoxide rebreathing technique at three time points: before SET, after SET and after the follow‐up period. After SET, stroke volume had increased by 10 (2–18) mL (mean (95% CI)), left atrial end‐diastolic volume by 10 (3–17) mL, and circumferential strain improved by 0.9%‐points (1.7–0.1) (all P < 0.05). At follow‐up, circumferential strain and left atrial end‐diastolic volume were reverted to baseline levels, while stroke volume remained elevated. Blood volume and morphological parameters for the left ventricle, including mass and end‐diastolic volume, did not change during the study. In conclusion, our findings demonstrate that a brief period of SET elicits beneficial central cardiac adaptations in elite ice hockey players independent of changes in blood volume. [ABSTRACT FROM AUTHOR]