Blue plaque review series: A.V. Hill, athletic records and the birth of exercise physiology

The Journal of Physiology, Год журнала: 2025, Номер unknown

Опубликована: Фев. 23, 2025

Abstract One hundred years ago, A.V. Hill authored three manuscripts analysing athletic world records from a physiological perspective. That analysis, grounded in Hill's understanding of contemporary muscle bioenergetics, provides fascinating sketch the thoughts and speculations one fathers exercise physiology. In this review, we reflect on prose with benefit 100 hindsight, illustrate how was able to draw startlingly accurate conclusions what limited data were available physiology intense exercise. discusses energetics running, swimming, rowing cycling both males females, as well addressing performance horses mechanics jumping. He also considers sports nutrition, pacing strategy ultra‐endurance Perhaps most impactfully, he establishes that speed–duration relationship has characteristics underlying basis performance. physiology, turn, differs depending duration event itself, providing first descriptions task‐dependent nature mechanisms limiting tolerance. A remarkable feature papers is they written just few before major revolution biochemistry, yet still develop conceptually sound ideas about human His hypotheses require only minor revision bring them into line current understanding. reaching their centenary, therefore, surprising these not have aged, but relevant remain. image

Язык: Английский

---

Neuromuscular and perceptual mechanisms of fatigue accompanying task failure in response to moderate-, heavy-, severe-, and extreme-intensity cycling

Journal of Applied Physiology, Год журнала: 2022, Номер 133(2), С. 323 - 334

Опубликована: Июнь 30, 2022

A comprehensive characterization of neuromuscular and perceptual mechanisms fatigue at task failure following exercise across the entire intensity spectrum is lacking. This study evaluated extent peripheral central fatigue, corresponding attributes, cycling within moderate-(MOD), heavy-(HVY), severe-(SVR), extreme-(EXT) domains. After a ramp-incremental test, 11 young males performed four constant-power output trials to limit tolerance (Tlim) 4 distinct domain-specific workloads. These were preceded followed by 5-s knee-extension maximal voluntary contractions (MVCs) femoral nerve electrical stimuli quantify fatigue. In addition, measures including ratings global legs pain, dyspnea, perceived effort (RPE) also collected. At Tlim, reductions in MVC independent (P > 0.05). However, was greater EXT SVR progressively, but distinctively, lower HVY MOD < Central similar after SVR, HVY, MOD, absent subjective progressively higher with intensities, whereas pain dyspnea intensities. On other hand, RPE EXT, not MOD. The findings demonstrate that highly domain-specific, not. Sensations such as may integrate sense determine manner specific each domain.NEW & NOTEWORTHY Together physiological responses, mechanisms, related accompanying are suggested be dependent on domain which sustained. Here, we show demonstrates high specificity, specificity for breathlessness demonstrated might have contributed reaching levels and, thus, failure.

Язык: Английский

---

Evaluating the Accuracy of Using Fixed Ranges of METs to Categorize Exertional Intensity in a Heterogeneous Group of Healthy Individuals: Implications for Cardiorespiratory Fitness and Health Outcomes

Sports Medicine, Год журнала: 2021, Номер 51(11), С. 2411 - 2421

Опубликована: Апрель 26, 2021

Язык: Английский

---

Cardiorespiratory Fitness and Performance Adaptations to High-Intensity Interval Training: Are There Differences Between Men and Women? A Systematic Review with Meta-Analyses

Sports Medicine, Год журнала: 2023, Номер 54(1), С. 127 - 167

Опубликована: Сен. 7, 2023

Abstract Background It is important to consider biological sex as a variable that might influence exercise adaptation in order optimize prescription for men and women. Objective The aim of this study was quantify the impact on maximal oxygen uptake ( $$\dot{V}$$ V˙ O 2max ) performance outcomes after high-intensity interval training (HIIT). Methods A systematic search review conducted by two independent reviewers up 8 September 2022 using MEDLINE, SPORTDiscus, Sports Medicine & Education Index ProQuest. Trials including healthy adults were included if they presented data or compared male female response HIIT. Performance measures concurrently measured physiological adaptations. Where appropriate, random-effects, pre-post meta-analysis undertaken. Data sub-grouped women, baseline level, mean age, intervention type, length. Heterogeneity assessed Chi 2 , Cochran’s Q Higgins I sensitivity analyses, where required. Study quality Newcastle–Ottawa Scale publication bias through visual inspection funnel plots. Results Thirty-three references from 28 trials n = 965; 462 women 503 men). Meta-analyses 19 studies eight peak power output testing (PPO), five threshold (power AT ). revealed similar increases g 0.57; 95% CI 0.44–0.69) 0.42–0.72), 0.38; 0.13–0.64) 0.11–0.64). Raw differences change Δ 0.32 L·min −1 3.50 mL·kg ·min men, versus 0.20 3.34 No significant present primary analysis any outcome. After sub-grouping, PPO effect size higher well-trained 0.37) with 0.17), interventions duration 4 weeks less had significantly smaller sizes those longer than p < 0.001). Unweighted percentage PPO, across 11.16 ± 7.39%, 5.99%, 8.07 6.55% 10.90 5.75%, 8.22 5.09%, 7.09 7.17% respectively. Significant heterogeneity both range: 62.06–78.80%). Sub-grouping status length decreased most groups. qualitative synthesis other indicated improvements fitness some evidence suggesting mechanisms adaptation. Limitations Risk Bias Publication unlikely have influenced results but could benefitted additional strengthen results. overlap age categories limits accuracy sub-grouping age. Conclusions Findings no sex-specific outcomes. Baseline accounted variability PROSPERO registration number: CRD42021272615.

Язык: Английский

---

The influence of skeletal muscle mitochondria and sex on critical torque and performance fatiguability in humans

The Journal of Physiology, Год журнала: 2023, Номер 601(23), С. 5295 - 5316

Опубликована: Окт. 30, 2023

Critical torque (CT) represents the highest oxidative steady state for intermittent knee extensor exercise, but extent to which it is influenced by skeletal muscle mitochondria and sex unclear. Vastus lateralis biopsy samples were collected from 12 females males -matched relative maximal oxygen uptake normalized fat-free mass (FFM) (F: 57.3 (7.5) ml (kg FFM)-1 min-1 ; M: 56.8 (7.6) P = 0.856) - prior CT determination performance fatiguability trials. Males had a lower proportion of myosin heavy chain (MHC) I isoform (40.6 (18.4)%) compared (59.5 (18.9)%; 0.021), MHC IIa IIx distributions protein markers mitochondrial content not different between sexes (P > 0.05). When maximum voluntary contraction (MVC), 42.9 (8.3)%; 37.9 (9.0)%; 0.172) curvature constant, W' 26.6 (11.0) N m s (N m)-1 26.4 (6.5) 0.962) significantly sexes. All biomarkers content, as well isoform, positively correlated with (0.48 < r 0.70; 0.05), (r 0.57; 0.007). Indices MVC- CT-controlled trials Greater abundance was associated attenuated declines in potentiated twitch exercise at 60% MVC 0.05); however, influence on reduced when prescribed CT. Whether these findings translate whole-body requires additional research. KEY POINTS: The quadriceps critical intensity an attainable, its relationship unknown. Matching facilitates investigations differences physiology, studies that have during ensured equal aerobic fitness Skeletal fatigue resistance performed torque. Differences torque, statistically significant. Our results suggest may contribute influencing exercise.

Язык: Английский

---

Interaction of Factors Determining Critical Power

Sports Medicine, Год журнала: 2023, Номер 53(3), С. 595 - 613

Опубликована: Янв. 9, 2023

Abstract The physiological determinants of high-intensity exercise tolerance are important for both elite human performance and morbidity, mortality disease in clinical settings. asymptote the hyperbolic relation between external power time to task failure, critical power, represents threshold intensity above which systemic intramuscular metabolic homeostasis can no longer be maintained. After ~ 60 years research into phenomenon a clear understanding its has emerged. purpose present review is critically examine this contemporary evidence order explain underpinnings power. Evidence demonstrating that alterations convective diffusive oxygen delivery impact upon first addressed. Subsequently, considered shows rates muscle utilisation, inferred via kinetics pulmonary consumption, influence data reveal picture flux along every step transport utilisation pathways It also influenced by motor unit recruitment patterns. On basis, it proposed act concert with determine intracellular milieu state fatigue within myocytes. This interacts exercising mass patterns ultimately

Язык: Английский

---

Durability in recreational runners: effects of 90-min low-intensity exercise on the running speed at the lactate threshold

European Journal of Applied Physiology, Год журнала: 2024, Номер unknown

Опубликована: Окт. 9, 2024

Recent studies have suggested that the capability to resist deterioration of physiological characteristics could be an independent factor contributing endurance performance. This study aimed at investigating whether prolonged low-intensity exercise induces shifts in lactate threshold, and fatigue-induced changes differ between sexes.

Язык: Английский

---

Slight power output manipulations around the maximal lactate steady state have a similar impact on fatigue in females and males

Journal of Applied Physiology, Год журнала: 2021, Номер 130(6), С. 1879 - 1892

Опубликована: Апрель 29, 2021

Neuromuscular fatigue (NMF) and exercise performance are affected by intensity sex differences. However, whether slight changes in power output (PO) below above the maximal lactate steady state (MLSS) impact NMF subsequent (time to task failure, TTF) is unknown. This study compared TTF females males response performed at MLSS, 10 W (MLSS-10) (MLSS+10). Twenty participants (9 females) three 30-min constant-PO bouts followed (1-min delay) a 80% of peak-PO. was characterized isometric voluntary contractions (IMVC) femoral nerve electrical stimulation knee extensors [e.g., peak torque potentiated high-frequency (Db100) single twitch (TwPt)] before immediately after bouts. IMVC declined less MLSS-10 (-18 ± 10%) MLSS (-26 14%) MLSS+10 (-31 11%; all P < 0.05), Db100 decline greater (-24 other intensities (MLSS-10: -15 9%; MLSS: -18 0.05). Females showed smaller reductions, relative baseline, TwPt (all this difference being not dependent on intensity. negatively impacted increasing PO (P 0.001), with no differences end-exercise > Slight manipulations around elicited great reduction force impairments contractile function. Although lower males, both sexes similarly.NEW & NOTEWORTHY It unknown minimum affect neuromuscular development males. The present data that decrease or increase relation function, respectively. Even though had an overall than similar intensity-dependent occurred independently sex.

Язык: Английский

---

Impact of training modes on fitness and body composition in women with obesity: A systematic review and meta‐analysis

Obesity, Год журнала: 2022, Номер 30(2), С. 300 - 319

Опубликована: Янв. 27, 2022

Abstract Objective This study aimed to assess the effectiveness of different exercise modalities and determine optimal prescription for improving cardiorespiratory fitness, body composition, metabolic health women with obesity. Methods A systematic review randomized controlled trials (RCTs) published between January 1988 October 2020 was conducted. The RCTs were screened using following inclusion criteria: 1) participants: aged 18 65 years BMI > 30 kg/m 2 without comorbidities; 2) intervention: exercise; 3) comparison: non‐intervention control; 4) outcomes measures: fitness (maximal oxygen consumption), composition (i.e., weight, percentage fat), and/or measures blood pressure, cholesterol). Results total 20 a 2,062 participants included. Although results showed that any form more effective than control, improvements in modest. Aerobic (vigorous moderate intensity) appeared most promising whereas low‐load resistance training resulted largest fatness. Conclusions In living obesity, aerobic consistently composition. both combined interventions appear promising, research is needed evaluate their efficacy an this population.

Язык: Английский

---

Sex-specific tuning of modular muscle activation patterns for locomotion in young and older adults

PLoS ONE, Год журнала: 2022, Номер 17(6), С. e0269417 - e0269417

Опубликована: Июнь 3, 2022

There is increasing evidence that including sex as a biological variable of crucial importance to promote rigorous, repeatable and reproducible science. In spite this, the body literature accounts for participants in human locomotion studies small often produces controversial results. Here, we investigated modular organization muscle activation patterns using concept synergies with double purpose: i) uncover possible sex-specific characteristics motor control ii) assess whether these are maintained older age. We recorded electromyographic activities from 13 ipsilateral muscles lower limb young adults both sexes walking (young old) running (young) on treadmill. The data set obtained 215 was elaborated through non-negative matrix factorization extract time-independent (i.e., modules) time-dependent primitives) coefficients synergies. found sparse modulations control. Motor modules showed different contribution hip extensors, knee extensors foot dorsiflexors various primitives were wider lasted longer) males propulsion synergy (but only not adults) weight acceptance running. Moreover, complexity similar younger sexes, but females compared males. essence, our results revealed existence defined differences way humans entirely

Язык: Английский

---