In this perspective paper, I re-examine the evidence base behind the common advice that older adults should " drink plenty of water before feeling thirsty " especially during heat exposure and exercise. I first discuss t...In this perspective paper, I re-examine the evidence base behind the common advice that older adults should " drink plenty of water before feeling thirsty " especially during heat exposure and exercise. I first discuss the seminal mechanistic studies that have shaped current thinking, with particular attention to their dominant experimental paradigms. I then contrast this foundation with more recent studies quantifying ad libitum drinking during prolonged heat exposure or exercise in older vs. younger adults. Finally, I outline key research priorities needed to refine hydration guidance for aging populations. Overall, the aim is to prompt a more critical appraisal of long-standing assumptions and to highlight that our knowledge in this area remains surprisingly limited.
PURPOSE: To investigate the impact of temporary cognitive load-induced changes in the size of the useful visual field of view (UFOV) on postural control during a quiet stance. METHODS: Twenty healthy young adults maintai...PURPOSE: To investigate the impact of temporary cognitive load-induced changes in the size of the useful visual field of view (UFOV) on postural control during a quiet stance. METHODS: Twenty healthy young adults maintained a quiet stance on a stable or an unstable surface while performing cognitive tasks under three levels of difficulty. Cognitive tasks and visual stimuli to assess the size of the UFOV were presented on a screen. The sway area, mean velocity, and sample entropy of the center of pressure in the anteroposterior and mediolateral directions were measured to assess postural control, and the reaction time to the visual stimulus was measured to assess the UFOV. RESULTS: The reaction time to visual stimuli was significantly delayed (661 ± 61 to 841 ± 76 ms, mean ± standard deviation), meaning the size of the UFOV shrank, while performing the cognitive tasks on the unstable surface. Moreover, sway area, mean velocity, and sample entropy (0.06 ± 0.02 to 0.05 ± 0.02) were significantly reduced. However, a significantly increased sample entropy (0.08 ± 0.03 to 0.09 ± 0.03) and decreased mean velocity were observed under the most challenging cognitive condition. A significantly negative correlation was observed between the temporary changes in the size of the UFOV and sample entropy changes (rho = − 0.519). CONCLUSION: The stability of the support surface and cognitive loads may temporarily change the size of the UFOV, which may affect postural control strategies.
Veldman MP, Kwant JZ, Lommerse J
… +7 more, Feenstra M, Lamoth CJC, Volkers AHM, Drenth H, Zuidema S, Bautmans I, Hobbelen H
Eur J Appl Physiol
· 2026 Jun · PMID 41770305
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PURPOSE: The supraspinal involvement in the control of passive movements remains elusive. Previous studies provided electromyographic evidence for speed and –type dependent changes in muscle activity. Based on mechanorec...PURPOSE: The supraspinal involvement in the control of passive movements remains elusive. Previous studies provided electromyographic evidence for speed and –type dependent changes in muscle activity. Based on mechanoreceptor properties, their age-related changes and the somatotopically organized connections between sensory and motor systems, this study aimed to provide electrophysiological evidence for the involvement of frontal cortex inhibition and corticomotor interactions in the control of passive movements. METHODS: Twenty healthy younger and older adults performed passive elbow flexion and extension movements at three metronome-based speeds (20, 60, and 100 beats per minute) in continuous and discontinuous fashion. The continuous condition included movements with no inter-movement pauses and the discontinuous conditions with pauses between flexion–extension transitions. The order of movement speeds increased progressively to prevent carryover effects in hypothesized resistance to passive movements from higher to lower speeds. In all conditions, electro-encephalographic and electromyographic data were acquired. Alpha power and beta corticomuscular coherence were used to quantify frontal cortex inhibition and brain-muscle connectivity, respectively. RESULTS: Frontal cortex inhibition decreased (p = 0.036) and brain-muscle connectivity increased (p < 0.001) with increasing movement speeds. In addition, frontal cortex inhibition was 17% higher in the discontinuous condition as compared to the continuous condition (p = 0.005) while corticomuscular coherence was 25.9% higher in the continuous vs. the discontinuous condition (p < 0.001). These effects were independent of age. CONCLUSION: Frontal cortex inhibition and brain-muscle interactions depend on passive movement speed and -type. The current data may provide insights into the processes underlying pathological muscle tone during passive movements.
Colomer-Poveda D, Mera-González I, Marcos-Frutos D
… +4 more, Botana-López L, Sánchez-Molina JA, López-Alonso V, Márquez G
Eur J Appl Physiol
· 2026 Jun · PMID 41770304
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PURPOSE: The aim of this triple-blind, placebo-controlled study was to determine the effects of anodal transcranial direct current stimulation (a-tDCS) applied over the primary motor cortex (M1) and the dorsolateral pref...PURPOSE: The aim of this triple-blind, placebo-controlled study was to determine the effects of anodal transcranial direct current stimulation (a-tDCS) applied over the primary motor cortex (M1) and the dorsolateral prefrontal cortex (DLPFC) on maximal voluntary force, the ability to repeat maximal handgrip contractions, cortical and corticospinal excitability measured with transcranial magnetic stimulation (TMS), and rating of perceived effort. METHODS: Forty-two healthy participants (19 women; 1 left-handed; 21.5 ± 1.4 years) completed three identical sessions differing only in the a-tDCS condition: 20 min of 2 mA a-tDCS over the M1, the DLPFC, and a sham session (30 s of real stimulation) in a randomized order. Maximal voluntary force, corticospinal excitability and intracortical inhibition and facilitation were assessed before (pre) and after (post) a-tDCS. Additionally, the number of maximal contractions performed until a 30% force loss in handgrip strength, and the overall perceived effort of the task were recorded following a-tDCS application. RESULTS: The results showed no significant main effects or interactions in any behavioural, neurophysiological, or perceptual variables, beyond a small but consistent reduction from pre to post measurements in maximal voluntary force (-3.2%) across all sessions. CONCLUSIONS: These findings indicate that a-tDCS over M1 or DLPFC does not improve maximal voluntary force, endurance during repeated maximal contractions, perceived effort or associated cortical and corticospinal excitability in healthy young adults (all results p > 0.05). Accordingly, in healthy young adults, the present results do not support recommending a-tDCS as a performance-enhancing intervention for maximal or repeated maximal muscle efforts.
Röijezon U, Hansson EE, Nae JÄ
… +2 more, Östlind E, Fransson PA
Eur J Appl Physiol
· 2026 Jun · PMID 41770303
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Immersive visual environment can deceive our interoceptive perception of how we move relative to our environment. If the visual environment or a high reliance on vision produces straining work conditions, motion sickness...Immersive visual environment can deceive our interoceptive perception of how we move relative to our environment. If the visual environment or a high reliance on vision produces straining work conditions, motion sickness or is associated with a medical disorder, the causes merit addressing. Therefore, the purpose of this study was to investigate whether postural control adapts to challenging visual environments from VR by adjusting postural stability and muscle co-contractions responses and investigate associations between stability measures and postural muscle co-contractions during VR-stimulation and control tests in quiet stance. Twenty-eight young adults participated (mean age 25.3 years, SD 4.6 years). In five sessions, they watched a VR simulation of a roller coast ride while a force platform recorded postural stability and electromyography recorded muscle co-contractions in leg muscles. Two control tests (quiet stance with eyes open and eyes closed), were performed before the VR sessions. The first VR session significantly increased the postural stability energy (p ≤ 0.002) and the muscle co-contraction levels (p ≤ 0.008) compared with the eyes open control test. Repeated VR sessions produced an adaptation that decreased postural stability energy (p ≤ 0.033) and muscle co-contraction levels (p ≤ 0.028). VR-stimulation made the association between postural stability responses and muscle co-contractions more prominent. Immersive visual environments can produce marked challenges to postural control, but the repeated experiences can also initiate sensory reweighting increasing resilience to visual disturbance.
Soares LL, Leite LB, Pelozin BRA
… +8 more, Costa SFF, Guimarães-Ervilha LO, da Silva RC, Machado-Neves M, Reis ECC, Fernandes T, Oliveira EM, Natali AJ
Eur J Appl Physiol
· 2026 Jun · PMID 41762275
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Calcium, sodium and potassium are essential for the contractile function of cardiomyocytes. In pulmonary arterial hypertension (PAH), intracellular calcium dynamics are impaired, affecting contractility and leading to he...Calcium, sodium and potassium are essential for the contractile function of cardiomyocytes. In pulmonary arterial hypertension (PAH), intracellular calcium dynamics are impaired, affecting contractility and leading to heart failure. Energy-dispersive X-ray spectroscopy associated with scanning electron microscopy (EDS-SEM) technique can be useful for mapping the distribution of these minerals in cardiac tissue. This study aimed to investigate chronic ionic imbalances in the cardiac tissue of a monocrotaline (MCT) induced PAH model, using EDS-SEM, and to evaluate the impact of these imbalances on the contractile function of isolated RV myocytes. Twenty-eight Wistar rats were assigned to Control and PAH groups, with PAH induced by MCT. Right ventricular (RV) function was assessed by echocardiography at day 24. On day 25, cardiac tissue was analyzed by EDS-SEM to quantify electrolytes and by Western blotting, and RV myocyte contractility was measured. Student's t-test was performed to compare the groups. Animals with PAH showed reduced final weight, increased cardiac and RV weight, and reduced RV systolic function compared to controls. EDS-SEM analysis revealed lower Ca and Na density in cardiac tissue of PAH animals. The expression of Ca regulatory proteins was reduced in the PAH group, and the contractility of isolated myocytes was impaired, exhibiting decreased amplitude, contraction velocity, and relaxation velocity. In conclusion, the study demonstrates that MCT-induced ionic imbalances, specifically reduced Ca and Na, disrupt excitation-contraction coupling proteins, leading to impaired cardiomyocyte contractility and contributing to the RV dysfunction observed in PAH.
This study assessed the feasibility and effectiveness of an 8-week individualized ischemic preconditioning protocol (IPC) combined with moderate physical activity to improve microvascular function and metabolic health in...This study assessed the feasibility and effectiveness of an 8-week individualized ischemic preconditioning protocol (IPC) combined with moderate physical activity to improve microvascular function and metabolic health in a physically inactive, high-risk population. Fifty sedentary adults (40–65 years) were randomized to IPC or sham control (sham), matched at baseline. Both groups completed an 8-week moderate walking program; the IPC group additionally received individualized IPC, while the sham group received a sham procedure. Biochemical markers and microvascular function assessed by post-occlusive reactive hyperaemia (PORH) were measured at baseline (T1), post-intervention (T2), and one-month follow-up (T3). Primary outcomes were fasting glucose, the triglyceride–glucose (TyG) index, and peak hyperaemic perfusion (RHmax). Significant group×time interactions indicated greater improvements with IPC for fasting glucose (ηp²=0.727, p < 0.001), TyG (ηp²=0.673, p < 0.001), and RHmax (ηp²=0.594, p < 0.001), with effects sustained at follow-up. Secondary biochemical outcomes also showed significant group×time interactions favoring IPC for HDL cholesterol (ηp²=0.503, p < 0.001), LDL cholesterol (ηp²=0.476, p < 0.001), total cholesterol (ηp²=0.752, p < 0.001), and triglycerides (ηp²=0.652, p < 0.001). Secondary PORH indices demonstrated IPC-related improvements in AOPmin (ηp²=0.152, p < 0.001), resting flow (ηp²=0.080, p = 0.018), time to peak (ηp²=0.594, p < 0.001), and recovery time (ηp²=0.208, p < 0.001), whereas AOP100 and biological zero did not differ between groups over time. Overall, individualized IPC combined with moderate walking was feasible and was associated with favourable changes in glycaemic status, lipid profile, and microvascular reactivity in this sample. These findings warrant confirmation in larger trials powered for clinically meaningful endpoints.
Buoite Stella A, D'Andrea F, Deodato M
… +5 more, Murena L, Sabot R, Martini M, Morrison SA, Ajčević M
Eur J Appl Physiol
· 2026 Jun · PMID 41762273
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PURPOSE: This study assessed sleep characteristics in a sample of experienced “hybrid” athletes (i.e., athletes who participate and train for competitions that combine endurance and resistance tasks, e.g., Hyrox, Cross-F...PURPOSE: This study assessed sleep characteristics in a sample of experienced “hybrid” athletes (i.e., athletes who participate and train for competitions that combine endurance and resistance tasks, e.g., Hyrox, Cross-Fit) to investigate the influence of training mode (i.e., resistance training and endurance training) on sleep quality, quantity, and architecture. METHODS: Eight male “Hyrox” athletes (23–32 years) wore a validated, non-invasive, ambulatory sleep monitoring device after completing either a primarily resistance or endurance training bout, performed within a two-week period, consisting of a total two resistance and two endurance post-training nights evaluated. Objectively-measured sleep parameters analysed included: total sleep time (TST), sleep onset latency (SOL), wake after sleep onset (WASO), sleep architecture (sleep stages proportion), and the number and duration of cardiac arousals occurring before and after sleep onset. RESULTS: Despite reporting ‘good’ overall sleep quality, hybrid athletes experienced shorter TST (~ 6.6 h) and spent ~ 5% less time in REM compared to reference non-athletes, but in-line with other sport populations. Compared to endurance training, resistance training was associated with longer SOL (29 vs. 10 min, p = 0.003) and shorter WASO (31 vs. 48 min, p = 0.008), with corresponding differences in cardiac arousals before and after sleep onset (13 vs. 5 events before SO, 81 vs. 99 events after SO, respectively, p = 0.006 and p = 0.010). CONCLUSION: Hybrid athletes presented sleep characteristics that differed depending on the training mode of their exercise bout. In particular, sleep latency and WASO time were positively associated with cardiac autonomic responses before and after sleep onset.
Eur J Appl Physiol
· 2026 Jun · PMID 41762271
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PURPOSE: To investigate the effects of caffeine (Caf) consumption and prior exercise on the validity of the Ekblom-Bak cycle test (EB-test) for estimating maximal oxygen uptake (VO₂max). METHODS: Healthy, habitual caffei...PURPOSE: To investigate the effects of caffeine (Caf) consumption and prior exercise on the validity of the Ekblom-Bak cycle test (EB-test) for estimating maximal oxygen uptake (VO₂max). METHODS: Healthy, habitual caffeine users received 250 mg Caf or placebo (Pla) in a double-blind randomised crossover design separated by one week. Each visit included two EB-tests performed before and after a maximal treadmill exercise (Ex). Heart rate (HR), blood pressure (BP), and oxygen uptake were measured, and estimation error was calculated as estimated-measured VO₂max. Data were analysed using repeated measures ANOVA with condition (Caf, Pla) and time (pre-Ex, post-Ex) as within-subject factors. RESULTS: Participants were 15 women and 17 men (33.5 ± 11.1 years). Resting HR and BP did not differ between trials, except for a modest increase in systolic BP after Caf (129 ± 14 mmHg vs. 122 ± 15 mmHg; p = 0.042). Maximal HR and VO₂max were unaffected, but time to exhaustion increased with caffeine (438 ± 73 s vs. 415 ± 69 s; p = 0.012). HR increased significantly from pre- to post-Ex, with no differences between Caf and Pla conditions. Estimation errors rose from pre- to post-Ex (-0.17 and - 0.12 L·min⁻¹ to - 0.28 and - 0.30 L·min⁻¹), independent of caffeine intake, body mass, or measured VO₂max. CONCLUSION: Caffeine did not affect the accuracy of the VO₂max estimation from the EB-test. However, strenuous exercise before testing increased estimation errors, suggesting that recent intense exercise has a greater impact on EB-test validity than moderate caffeine consumption.
PURPOSE: Oxygen deficit (O2 deficit) and post-exercise oxygen uptake ([Formula: see text]O2) recovery responses are clinical prognostic markers in cardiac patients but have not been studied after exercise training in pat...PURPOSE: Oxygen deficit (O2 deficit) and post-exercise oxygen uptake ([Formula: see text]O2) recovery responses are clinical prognostic markers in cardiac patients but have not been studied after exercise training in patients with coronary heart disease (CHD). We aimed to compare the effects of different modalities of exercise training on O2 deficit and post-exercise [Formula: see text]O2 responses in CHD patients. METHODS: From a pooled analysis of three randomised control trial, patients with CHD were trained with moderate-intensity continuous exercise training (MICET), low volume high-intensity interval training (LV-HIIT), or combined MICET/HIIT for 12 weeks. Cardiopulmonary exercise test (CPET) parameters were assessed, and key exercise variables were calculated during and after exercise. O2 deficit, CPET post-exercise kinetics time constant for oxygen uptake ([Formula: see text]O2), carbon dioxide ([Formula: see text]CO2), minute ventilation ([Formula: see text]E) and heart rate (τHR), O2 debt and [Formula: see text]O2 recovery delay (RD) were calculated before and after training. RESULTS: A significant training effect for [Formula: see text]O2 (p < 0.05) was shown for all groups. Shorter [Formula: see text]O2 values with small effect size (ES from 0.21 to 0.4) were noted for the combined MICET/HIIT and MICET groups. A significant training effect (p < 0.01) was noted for O2 debt that was increased after training (ES: 0.1 to 0.47). No significant statistical effect was shown for [Formula: see text]O2 RD and [Formula: see text]CO2, [Formula: see text]E, τHR and O2 deficit in all groups. CONCLUSIONS: In patients with CHD, exercise training improved post-exercise [Formula: see text]O2 kinetic and the O2 debt, with a higher impact of exercise dose (combined MICET/HIIT). Exercise training did not improve the [Formula: see text]O2 RD or the recovery time constant value of other cardiorespiratory parameters in CHD patients. TRIAL REGISTRATION: NCT03414996, NCT02048696, NCT03443193.
Eur J Appl Physiol
· 2026 Jun · PMID 41739166
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PURPOSE: Recent discoveries indicate neurophysiological mechanisms might underlie pain symptoms and knee extension strength deficits in patellar tendinopathy. Specifically, reduced spinal excitability could underlie stre...PURPOSE: Recent discoveries indicate neurophysiological mechanisms might underlie pain symptoms and knee extension strength deficits in patellar tendinopathy. Specifically, reduced spinal excitability could underlie strength deficits, while a proportion of individuals exhibit altered endogenous pain modulation. Parallels can be drawn to other persistent knee conditions where links between pain and motor neurophysiological mechanisms have been established. Whether similar neural mechanism interplay occurs in patellar tendinopathy has not yet been investigated. We aimed to determine whether endogenous pain modulation was associated with motor neurophysiological outcomes in patellar tendinopathy. METHODS: We included n = 19 athletes with patellar tendinopathy who participated in two cross-sectional studies; one assessing endogenous pain modulation, and the other motor neurophysiological function. We quantified pain inhibition as pressure pain threshold change immediately following 120-seconds hand immersion in painful cold-water, while pain facilitation was calculated as hand-pain change from five to 20 s. Following knee extension MVIF assessment, we used transcranial magnetic stimulation (TMS) to measure corticospinal excitability and inhibition via production of motor evoked potentials and their silent period. Additionally, we collected lumbar-evoked potentials (LEPs) to quantify spinal excitability. We could only collect TMS and LEP outcomes in n = 15 and n = 17 participants, respectively. RESULTS: Greater pain facilitation predicted higher LEP (indicating lower spinal excitability) (β = 38.4 [95%CI 10.3–77.0]) and reduced strength (β=-7.9 [95%CI − 15.1 to − 2.6]). Pain inhibition was not associated with motor neurophysiological outcomes (p > 0.05). CONCLUSION: Our findings provide preliminary evidence of interplay between the neurophysiological mechanisms underlying pain facilitation and knee extension strength deficits in patellar tendinopathy.
PURPOSE: During ascent to and residence at high altitude, plasma volume (PV) is reduced, and hemoglobin mass (Hbmass) subsequently increases, protecting blood oxygen content. Acclimatized native Tibetan highlanders (TH,...PURPOSE: During ascent to and residence at high altitude, plasma volume (PV) is reduced, and hemoglobin mass (Hbmass) subsequently increases, protecting blood oxygen content. Acclimatized native Tibetan highlanders (TH, i.e., Sherpa ethnic group) residing at high altitude are known to have higher PV than lowlanders (LL), reducing blood viscosity. However, little is known about differences in PV and Hbmass responses between unacclimatized TH and LL during early acclimatization. We aimed to compare PV and Hbmass between acclimatizing TH and LL during an ascent to high altitude over 8–9 days. METHODS: We recruited age- and sex-matched unacclimatized participants at 1400 m (14TH, 14LL), who performed a 5-day incremental ascent to 4300 m. Before ascent (1400 m) and on days 8–9 of the expedition (days 3–4 after arrival at 4300 m), venous blood samples were obtained for hemoglobin concentration ([Hb]). Hbmass and blood volumes were determined via CO-rebreathing. RESULTS: At 1400 m, there were no differences between groups in [Hb], Hbmass, and blood volumes normalized for body weight (P ≥ 0.24). Relative PV was decreased at 4300 m (40.9 ± 4.5 to 34.1 ± 5.5 mL.kg−1, P = 0.001, d = − 0.90), while there was a trivial increase in relative Hbmass (9.76 ± 1.82 to 10.00 ± 1.99 g.kg−1, p = 0.0494, d = 0.12). These led to an increase in [Hb] (131 ± 11 to 149 ± 10 g.dL−1, P = 0.001, d = 1.33). These changes were similar for both groups (interaction effect: P > 0.80). CONCLUSION: Hematological changes during early acclimatization did not differ between acclimatizing TH and LL, indicating that hematological acclimatization is not a differentiating physiological factor during early ascent to high altitude.
PURPOSE: Neuromuscular properties have been well-studied in three of the four muscles of the quadriceps femoris. However, lack of accessibility of the vastus intermedius (VI) due to its deep location has precluded compre...PURPOSE: Neuromuscular properties have been well-studied in three of the four muscles of the quadriceps femoris. However, lack of accessibility of the vastus intermedius (VI) due to its deep location has precluded comprehensive insight on motor unit (MU) properties. Thus, the purpose here was to compare the MU firing rates of the VI and vastus lateralis (VL). METHODS: In ten young participants (3 females), ultrasound-guided intramuscular tungsten microelectrodes were used to record MU firing rates from the VI and VL during non-fatiguing contractions at four intensities, including during maximal efforts. RESULTS: Maximal knee extension torque was 518 ± 113 N with voluntary activation of over 90%. A total of 2741 MU trains were sampled with equal numbers from both muscles. There was a linear relationship between contractile intensity and mean MU firing rate in both the VI and VL (r = 0.79 and 0.81; P < 0.001), and rates ranged from ~ 8 Hz at 10% to ~ 27 Hz at maximum with no difference between the two muscles (P = 0.45) at any force level (P = 0.08). CONCLUSION: Despite, differences in anatomical and muscular architecture allowing for varying contributions to knee extension, MU firing rates were similar between the VI and VL. This indicates at the motor unit level that fundamental neural activation strategies between the two larger torque generating muscles of the quadriceps may be similar based on mean MU firing rates. Any variation in the relative contributions to knee extensor torque from these synergists may be governed more by biomechanical factors rather than apparent motor unit firing rate.
Eur J Appl Physiol
· 2026 Jun · PMID 41739162
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PURPOSE: The safe upper limits of weekly exercise participation during pregnancy, as well as the modifications active individuals make to their weekly exercise behaviours while pregnant, are unclear. This retrospective o...PURPOSE: The safe upper limits of weekly exercise participation during pregnancy, as well as the modifications active individuals make to their weekly exercise behaviours while pregnant, are unclear. This retrospective observational study aimed to determine how active individuals modify their training behaviours before, during, and after pregnancy. METHODS: We analysed data from 21 participants (aged 26-41 at the time of survey completion) who were physically active prior to their most recent pregnancy. Participants shared the exercise data recorded using a fitness application or monitoring device before, during, and after pregnancy. Participants also completed surveys about maternal and neonatal health outcomes. We used mixed-effects models to analyse weekly changes in participants' total exercise duration, session duration, exercise frequency, and aerobic exercise intensity and volume. RESULTS: Most participants (n = 19) exercised above recommended weekly durations (i.e., > 300 min.wk) during at least one week of pregnancy. However, weekly exercise duration progressively decreased throughout the antenatal period, and increased during the first 12 weeks postpartum. All infants were born within the normal birthweight range (2500 to 4500 g), and 14 were born at full term (early term n = 5, late preterm n = 2). CONCLUSION: Our findings highlight that active pregnant individuals exceed weekly exercise recommendations, yet adapt their training load throughout pregnancy. These findings emphasise the importance of considering physical activity recommendations as relative in nature, and interpreting them in the context of previous exercise behaviours. Exercise professionals should provide individualised support to active individuals in their pregnancy and postpartum journeys.
This study investigated the effects of a short-term, low-volume eccentric training protocol on knee extensor strength and thickness in untrained young men, including the potential cross-education effect. Twenty-six healt...This study investigated the effects of a short-term, low-volume eccentric training protocol on knee extensor strength and thickness in untrained young men, including the potential cross-education effect. Twenty-six healthy male participants with no resistance training experience were assigned to the training (n = 14) or control (n = 12) group. The training group performed five maximal voluntary eccentric contractions of the knee extensors on the dominant leg, twice weekly for 2 weeks. Maximal voluntary contraction torque in isometric (MVIC), concentric (MVCC), and eccentric (MVEC) modes, along with quadriceps muscle thickness, were measured before and after the intervention. Significant increases in the MVIC (15.7% ± 24.8%, d = 0.66), MVCC (8.8% ± 7.3%, d = 0.65), and MVEC (22.1% ± 16.4%, d = 0.87) torques were observed in the trained legs (all p < 0.05). MVIC, MVCC, and MVEC torque showed no significant changes in the untrained legs and the control group. The muscle thickness remained unchanged across all groups. In conclusion, a 2-week protocol involving five maximal eccentric contractions twice weekly effectively increased knee-extensor strength in untrained individuals, while no hypertrophic changes were detected. However, the minimal protocol did not elicit cross-education, suggesting that a higher training volume or longer duration may be necessary to induce this effect. Such a time-efficient strategy may be suitable for early-stage rehabilitation or for populations with limited training capacity.
BACKGROUND: Safe and effective ergogenic strategies remain a challenge in elite Paralympic sports. Oxytocin, a neuropeptide linked to stress regulation and energy metabolism, has emerged as a potential modulator of exerc...BACKGROUND: Safe and effective ergogenic strategies remain a challenge in elite Paralympic sports. Oxytocin, a neuropeptide linked to stress regulation and energy metabolism, has emerged as a potential modulator of exercise responses. OBJECTIVE: To examine the effects of intranasal oxytocin on hormonal, neuromuscular, and thermal responses in Paralympic powerlifting athletes. METHODS: Eleven athletes completed a randomized, double-blind, placebo-controlled trial, performing a traditional strength session (5 × 5 at 80% 1RM). Total testosterone (TT), free testosterone (FT), cortisol, dynamic strength at submaximal load (45% 1RM), and skin temperature (thermography) were assessed. RESULTS: In the placebo condition, TT increased from post to 24 h (310.18 → 394.18 ng/dL; p = 0.024), while cortisol decreased from pre to post (10.07 → 6.72 µg/dL; p = 0.011). Under oxytocin, cortisol fell acutely (9.52 → 6.48 µg/dL; p = 0.002) with partial recovery at 24 h (8.73 µg/dL; p = 0.039). The TT/C ratio rose only in placebo at 24 h (p = 0.046). Oxytocin preserved velocity and power at 45% 1RM and attenuated prolonged skin temperature elevations in key muscles. CONCLUSION: Oxytocin acted as a multifactorial modulator, enhancing hormonal balance, submaximal performance, and peripheral recovery, suggesting potential as an ergogenic aid in Paralympic powerlifting.