Peñailillo, L, Aedo, C, Cartagena, M, Contreras, A, Reyes, A, Ramirez-Campillo, R, Earp, JE, and Zbinden-Foncea, H. Effects of eccentric cycling performed at long vs. short muscle lengths on heart rate, rate perceived effort, and muscle damage markers. J Strength Cond Res 34(10): 2895-2902, 2020-It is possible that the magnitude of muscle damage in eccentric cycling is dependent on seat position that could affect the muscle length changes during eccentric contractions. However, no previous study has investigated the effect of seat position on muscle damage and metabolic demand in eccentric exercise. Thus, this study compared 2 seating positions; seat forward in which knee extensor muscles were stretched longer (LONG) and seat back in which the muscles were stretched shorter (SHORT). Young men performed 30 minutes of eccentric cycling at 80% of maximal concentric power output at either LONG (n = 10) or SHORT (n = 10) condition. Heart rate and rate perceived effort (RPE) during exercise, changes in maximal voluntary isometric contraction (MVC) strength of the knee extensors, muscle soreness assessed by a visual analog scale (VAS), and pressure-pain threshold (PPT) before, immediately after, and 24-72 hours after exercise were compared between conditions. Heart rate and RPE were significantly greater in LONG than SHORT group (9.5 and 19.0%, respectively). Post-exercise reduction in MVC was 8.4-14.0% greater in LONG than SHORT group from immediately after to 48 hours after exercise. In addition, VAS was greater in LONG than SHORT group from 48 to 72 hours after exercise, and vastus medialis PPT was greater in SHORT than LONG group from 24 to 72 hours after exercise (p < 0.05). These results suggest that muscle damage and metabolic demand are greater when seat is set back than forward. Thus, when prescribing eccentric cycling to individuals who are unaccustomed to eccentric cycling, it is better to set the seat far from the pedals.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1519/JSC.0000000000002732 | DOI Listing |
Eur J Appl Physiol
December 2024
LFE Research Group, Department of Health and Human Performance. Faculty of Physical Activity and Sport Sciences, Universidad Politécnica de Madrid, Calle de Martín Fierro, 7, 28040, Madrid, Spain.
Purpose: To investigate the acute effects of eccentric-based resistance exercise and sex-hormone fluctuations on P1NP and β-CTX-1 concentrations in premenopausal females.
Methods: Nine eumenorrheic females and ten oral contraceptive (OC) users performed eccentric-based resistance exercise, consisted of 10 × 10 repetitions of parallel back squats with a 4-s eccentric phase, in the early-follicular (EFP), late-follicular (LFP) and mid-luteal (MLP) phases of the menstrual cycle (MC) or in the withdrawal (WP) and active pill-taking (APP) phases of the OC cycle.
Results: 17β-oestradiol (pg·ml) was lower in EFP (36.
Proc Natl Acad Sci U S A
December 2024
Institute for Astronomy, University of Hawaii, Honolulu, HI 96822.
Small bodies are capable of delivering essential prerequisites for the development of life, such as volatiles and organics, to the terrestrial planets. For example, empirical evidence suggests that water was delivered to the Earth by hydrated planetesimals from distant regions of the Solar System. Recently, several morphologically inactive near-Earth objects were reported to experience significant nongravitational accelerations inconsistent with radiation-based effects, and possibly explained by volatile-driven outgassing.
View Article and Find Full Text PDFJ Sports Med Phys Fitness
December 2024
Department of Life Science, The University of Tokyo, Meguro, Japan -
Background: Joint stiffness endurance is considered essential in many sports events. We previously reported that reduced joint stiffness due to repetitive hopping was associated with reduced active muscle stiffness. However, the determinants of active muscle stiffness endurance were unknown.
View Article and Find Full Text PDFNat Commun
December 2024
University of Southampton, Waterfront Campus, National Oceanography Centre Southampton, Southampton, UK.
Earth's obliquity and eccentricity cycles are strongly imprinted on Earth's climate and widely used to measure geological time. However, the record of these imprints on the oxygen isotope record in deep-sea benthic foraminifera (δO) shows contradictory signals that violate isotopic principles and cause controversy over climate-ice sheet interactions. Here, we present a δO record of high fidelity from International Ocean Drilling Program (IODP) Site U1406 in the northwest Atlantic Ocean.
View Article and Find Full Text PDFJ Sci Med Sport
November 2024
Allied Health and Human Performance Unit, University of South Australia, Australia; School of Health Sciences, Swinburne University of Technology, Australia.
Objectives: To describe the acute effects of exercise on the morphology, mechanical properties and blood flow of the Achilles tendon, as measured with ultrasound.
Design: Systematic review of cohort studies.
Methods: Seven electronic research databases were systematically searched for exercise intervention-based studies reporting morphology, mechanical properties and blood flow of the Achilles tendon, as measured with ultrasound.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!