The effects of training with high-speed interval running on muscle performance are modulated by slope

© 2021 The Authors. Published by Wiley. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.14814/phy2.14656We examined changes in selected muscle performance parameters after 8 weeks of interval training using two opposite running inclinations. We hypothesized that the uphill training will affect endurance muscle performance outcomes, whereas the downhill training will affect power muscle performance outcomes. Fourteen physically active volunteers were randomly assigned into either the Uphill group (UG; n = 7; uphill interval running at +10% incline) or the Downhill group (DG; n = 7; downhill interval running at -10% incline) and completed 16 training sessions. Each session consisted of ten 30 s treadmill runs at 90% of maximum aerobic speed (MAS) with a work to rest ratio of 1:2. Vertical jump performance, isometric (MVC) and isokinetic torque of knee extensors and flexors, and fatigue of knee extensors were evaluated pre and post-training. Moreover, body composition (via bioimpedance) and vastus lateralis muscle architecture (via ultrasonography) were assessed pre and post-training. Relative lean tissue mass, relative fat mass, and squat jump (cm) significantly (p < .05) changed from baseline values by +4.5 ± 4.0%, -11.5 ± 9.6%, and +9.5 ± 11.7%, respectively, only in the DG. Similarly, DG improved absolute values of knee extension rate of torque development and impulse (p < .05), whereas knee flexion peak torque angle significantly decreased in both groups (p < .05). On the other hand, the UG increased the number of repetitions achieved during the fatigue protocol and total work by 21.2 ± 32.6% and 13.8 ± 21.2%, respectively (p < .05). No differences were found between groups in muscle architecture. Introducing variations in slope during HIIT could be used to induce specific improvements toward muscle endurance or power performance characteristics.Published versio

Human white-fat thermogenesis: Experimental and meta-analytic findings

© 2020 The Authors. Published by Taylor & Francis. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1080/23328940.2020.1769530White adipose tissue (WAT) thermogenic activity may play a role in whole-body energy balance and two of its main regulators are thought to be environmental temperature (Tenv) and exercise. Low Tenv may increase uncoupling protein one (UCP1; the main biomarker of thermogenic activity) in WAT to regulate body temperature. On the other hand, exercise may stimulate UCP1 in WAT, which is thought to alter body weight regulation. However, our understanding of the roles (if any) of Tenv and exercise in WAT thermogenic activity remains incomplete. Our aim was to examine the impacts of low Tenv and exercise on WAT thermogenic activity, which may alter energy homeostasis and body weight regulation. We conducted a series of four experimental studies, supported by two systematic reviews and meta-analyses. We found increased UCP1 mRNA (p = 0.03; but not protein level) in human WAT biopsy samples collected during the cold part of the year, a finding supported by a systematic review and meta-analysis (PROSPERO review protocol: CRD42019120116). Additional clinical trials (NCT04037371; NCT04037410) using Positron Emission Tomography/Computed Tomography (PET/CT) revealed no impact of low Tenv on human WAT thermogenic activity (p > 0.05). Furthermore, we found no effects of exercise on UCP1 mRNA or protein levels (p > 0.05) in WAT biopsy samples from a human randomized controlled trial (Clinical trial: NCT04039685), a finding supported by systematic review and meta-analytic data (PROSPERO review protocol: CRD42019120213). Taken together, the present experimental and meta-analytic findings of UCP1 and SUVmax, demonstrate that cold and exercise may play insignificant roles in human WAT thermogenic activity. Abbreviations: WAT:White adipose tissue; Tenv: Environmental temperature; UCP1: Uncoupling protein one; BAT: Brown adipose tissue; BMI:Body mass index; mRNA: Messenger ribonucleic acid; RCT: Randomized controlled trial; WHR: Waist-to-hip ratio; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-analyses; PET/CT: Positron Emission Tomography and Computed Tomography; REE: Resting energy expenditure; 18F-FDG: F18 fludeoxyglucose; VO2peak:Peak oxygen consumption; 1RM: One repetition maximum; SUVmax: Maximum standardized uptake value; Std: Standardized mean difference.This work was supported by funding from the European Union 7th Framework Program FP7-PEOPLE-2012-IRSES grant no. [319010]; FP7-PEOPLE-2013-IRSES grant no. [612547] and Horizon 2020 ICI-THROUGH grant no [645710].Published versio

Predictors of the experience of a Cytosponge test: analysis of patient survey data from the BEST3 trial

Availability of data and materials: The trial protocol, statistical analysis plan, and statistical report are available via the University of Cambridge data repository (https://www.data.cam.ac.uk/repository). Datasets will be available from R Fitzgerald ([email protected]) on request.Copyright © The Author(s) 2023. Background: The Cytosponge is a cell-collection device, which, coupled with a test for trefoil factor 3 (TFF3), can be used to diagnose Barrett’s oesophagus, a precursor condition to oesophageal adenocarcinoma. BEST3, a large pragmatic, randomised, controlled trial, investigated whether offering the Cytosponge-TFF3 test would increase detection of Barrett’s. Overall, participants reported mostly positive experiences. This study reports the factors associated with the least positive experience. Methods: Patient experience was assessed using the Inventory to Assess Patient Satisfaction (IAPS), a 22-item questionnaire, completed 7–14 days after the Cytosponge test. Study cohort: All BEST3 participants who answered ≥ 15 items of the IAPS (N = 1458). Statistical analysis: A mean IAPS score between 1 and 5 (5 indicates most negative experience) was calculated for each individual. ‘Least positive’ experience was defined according to the 90th percentile. 167 (11.4%) individuals with a mean IAPS score of ≥ 2.32 were included in the ‘least positive’ category and compared with the rest of the cohort. Eleven patient characteristics and one procedure-specific factor were assessed as potential predictors of the least positive experience. Multivariable logistic regression analysis using backwards selection was conducted to identify factors independently associated with the least positive experience and with failed swallow at first attempt, one of the strongest predictors of least positive experience. Results: The majority of responders had a positive experience, with an overall median IAPS score of 1.7 (IQR 1.5–2.1). High (OR = 3.01, 95% CI 2.03–4.46, p < 0.001) or very high (OR = 4.56, 95% CI 2.71–7.66, p < 0.001) anxiety (relative to low/normal anxiety) and a failed swallow at the first attempt (OR = 3.37, 95% CI 2.14–5.30, p < 0.001) were highly significant predictors of the least positive patient experience in multivariable analyses. Additionally, sex (p = 0.036), height (p = 0.032), alcohol intake (p = 0.011) and education level (p = 0.036) were identified as statistically significant predictors. Conclusion: We have identified factors which predict patient experience. Identifying anxiety ahead of the procedure and discussing particular concerns with patients or giving them tips to help with swallowing the capsule might help improve their experience. Trial registration ISRCTN68382401.The BEST3 trial was funded by Cancer Research UK (C14478/A21047), National Institute for Health Research covering service support costs, the UK National Health Service funding excess treatment costs and Medtronic providing funding for Cytosponge devices and TFF3 antibodies. RCF is funded by a Programme Grant from the Medical Research Council (RG84369) and is CI for the BEST3 trial and the Innovate UK funded DELTA study. JO was supported by PDS’s Cancer Research UK programme Grant (C8162/A16892) and is currently supported by the Barts Charity (EMSG1K1R). RM was supported by PDS’ Cancer Research UK Cancer Prevention Clinical Trials Unit funding (Grant No.: C8162/A25356). SGS is supported by a Yorkshire Cancer Research Fellowship. JW is funded by a Cancer Research UK career development fellowship (C7492/A17219). BG was funded as part of the DELTA study by Innovate UK (Grant No. 41162). FW is supported by the Cancer Research UK CanTest Grant [C8640/A23385]. RL is supported by the Intramural Research Program of the US National Institutes of Health/National Cancer Institute

Body composition and 6 minute walking ability in late-onset pompe disease patients after 9 years of enzyme replacement therapy

Objective: Pompe disease is a rare autosomal recessive disorder caused by the deficiency of acid α-glycosidase resulting in accumulation of glycogen in the lysosomes. The late-onset form of the disease (LOPD) causes primarily progressive muscle weakness and respiratory insufficiency. Enzyme replacement therapy (ERT) introduced in 2006, showed mild improvement or stabilization of the symptoms although long-term data are limited. Aim of the study was to describe the progression of body composition and walking ability in LOPD patients receiving ERT consistently for 9 years. Methods: Lean body mass, bone mineral density, body fat and 6 min walking distance were assessed in three male and three female LOPD patients (height 165.8 ± 11.2 cm, age 42.3 ± 11.8yrs, body mass 71.1 ± 20.8 kg, at study entry), every three years, for 9 years since ERT initiation (T0, T3, T6, T9). Results: Total body and upper extremities’ lean mass remained unchanged (p &lt; 0.05), but it was decreased for the lower extremities (T3:13.06 ± 3.848 kg vs. T9:11.63 ± 3.49 kg, p &lt; 0.05). Lean body mass was not significantly different after 9 years of ERT compared to before the ERT initiation (T0 to T9). Bone mineral density remained unchanged. Percent body fat increased (T0:39.1 ± 10.3%, vs. T9:43.1 ± 10.4%, p &lt; 0.05). Six minute walking distance tended to increase after 3 years of ERT and decreased gradually thereafter, with no difference between T0-T9. Lean mass of the lower extremities adjusted for body weight was significantly correlated with 6 min walking distance (r = 0.712, p &lt; 0.05). Conclusion: The current data show that enzyme replacement therapy may preserve lean body mass, bone mineral density and walking capacity in LOPD patients. © 2020 Informa UK Limited, trading as Taylor &amp; Francis Group

Triceps brachii muscle strength and architectural adaptations with resistance training exercises at short or long fascicle length

The aim of this study was to investigate whether resistance training at short or long triceps brachii fascicle length induces different muscular strength and architectural adaptations. Nine young, novice, female participants, were trained for 6 weeks (two sessions/week) performing 6 sets × 6-RM (repetition maximum) unilateral cable exercises either with push-downs at short fascicle length (S) or overhead extensions with the contralateral arm at long fascicle length (L) of triceps brachii. Before and after training, 1-RM elbow extension and triceps brachii muscle architecture were evaluated. Muscle architecture was analyzed at 50% and 60% of the upper-arm length. Two-dimensional longitudinal muscle area of the triceps long head was also analyzed. The results indicated that 1-RM increased 40.1 ± 21.3% and 44.5 ± 20.1% (p < 0.01) after S and L, respectively. Muscle thickness at 50% length was increased 10.7 ± 15.3% (p < 0.05) and 13.7 ± 9.0% (p < 0.01) after S and L, while at 60% it was increased 15.5 ± 18.8% (p < 0.05) and 19.4 ± 16.3% (p < 0.01), respectively. Longitudinal muscle area increased similarly after S and L (p < 0.01). Fascicle angle and length were not altered with training. These results indicate that muscle strength and architecture of elbow extensors adapt similarly during the first six weeks of resistance training at either long or short fascicle length. © 2018 by the authors

Effects of tapering with light vs. heavy loads on track and field throwing performance

The purpose of the study was to investigate the effects of power training with light vs. heavy loads during the tapering phases of a double periodized training year on track and field throwing performance. Thirteen track and field throwers aged 16-26 years followed 8 months of systematic training for performance enhancement aiming at 2 tapering phases during the winter and the spring competition periods. Athletes performed tapering with 2 different resistance training loads (counterbalanced design):7 athletes used 30% of 1 repetition maximum (1RM) light-load tapering (LT), and 6 athletes used the 85% of 1RM heavy-load tapering (HT), during the winter tapering. The opposite was performed at the spring tapering. Before and after each tapering, throwing performance, 1RM strength, vertical jumping, rate of force development (RFD), vastus lateralis architecture, and rate of perceived exertion were evaluated. Throwing performance increased significantly by 4.8 ± 1.0% and 5.6 ± 0.9% after LT and HT, respectively. Leg press 1RM and squat jump power increased more after HT than LT (5.9 ± 3.2% vs. 23.4 ± 2.5%, and 5.1 ± 2.4% vs. 0.9 ± 1.4%, respectively, p ≤ 0.05). Leg press RFD increased more in HT (38.1 ± 16.5%) compared with LT (22.9 ± 6.7%), but LT induced less fatigue than HT (4.0 ± 1.5 vs. 6.7 ± 0.9, p ≤ 0.05). Muscle architecture was not altered after either program. These results suggest that performance increases similarly after tapering with LT or HT in track and field throwers, but HT leads to greater increases in strength, whole body power, and RFD. © 2014 National Strength and Conditioning Association

Rate of Force Development, Muscle Architecture, and Performance in Young Competitive Track and Field Throwers

The rate of force development (RFD) is an essential component for performance in explosive activities, although it has been proposed that muscle architectural characteristics might be linked with RFD and power performance. The purpose of the study was to investigate the relationship between RFD, muscle architecture, and performance in young track and field throwers. Twelve young track and field throwers completed 10 weeks of periodized training. Before (T1) and after (T2) training performance was evaluated in competitive track and field throws, commonly used shot put tests, isometric leg press RFD, 1 repetition maximum (1RM) strength as well as vastus lateralis architecture and body composition. Performance in competitive track and field throwing and the shot put test from the power position increased by 6.76 ± 4.31% (p &lt; 0.001) and 3.58 ± 4.97% (p = 0.019), respectively. Rate of force development and 1RM strength also increased (p ≤ 0.05). Vastus lateralis thickness and fascicle length increased by 5.95 ± 7.13% (p = 0.012) and 13.41 ± 16.15% (p = 0.016), respectively. Significant correlations were found at T1 and T2, between performance in the shot put tests and both RFD and fascicle length (p ≤ 0.05). Close correlations were found between RFD, muscle thickness, and fascicle length (p ≤ 0.05). Significant correlations were found between the % changes in lean body mass and the % increases in RFD. When calculated together, the % increase in muscle thickness and RFD could predict the % increase in shot put throw test from the power position (p = 0.019). These results suggest that leg press RFD may predict performance in shot put tests that are commonly used by track and field throwers. © 2015 National Strength and Conditioning Association