This study tested the hypothesis that the first exercise bout consisting of slow-velocity (30° · s(-1)) maximal lengthening contractions would not affect muscle damage in a subsequent bout consisting of fast-velocity (210° · s(-1)) lengthening contractions. Eighteen men were randomly assigned into either a repeated bout group (n = 10) or control group (n = 8). The repeated bout group performed 2 bouts of exercise consisting of 210 maximal lengthening contractions of the elbow flexors separated by 14 days at a velocity of 30° · s(-1) for the first and 210° · s(-1) for the second bout. The control group performed a single bout of the fast-velocity exercise. Changes in maximal isometric strength, range of motion (ROM), upper-arm circumference, muscle thickness, muscle soreness, serum creatine kinase, and lactate dehydrogenase activities were measured before, immediately after, and 24 to 96 hours after exercise. The repeated bout group showed significantly (p < 0.05) smaller changes in all criterion measures except for muscle soreness after the fast-velocity exercise compared with the control group. A significant (p < 0.05) difference was evident only for ROM between the slow- and fast-velocity bouts of the repeated bout group. These results suggest that slow-velocity exercise reduced muscle damage induced by fast-velocity exercise, although the reduction was not large.

Download full-text PDF

Source
http://dx.doi.org/10.1519/JSC.0b013e3181bac2bdDOI Listing

Publication Analysis

Top Keywords

lengthening contractions
20
repeated bout
16
bout group
16
muscle damage
12
control group
12
fast-velocity exercise
12
damage induced
8
induced fast-velocity
8
bout
8
bout consisting
8

Similar Publications

While the importance of the upper and lower limbs in locomotion is well understood, the kinematics of the trunk during walking remains largely unexplored. Two decades ago, a casual observation was reported indicating spine lengthening in a small sample of mostly children during walking, but this observation was never replicated. Objectives: This study aims to verify the preliminary observation that spine lengthening occurs during walking and to explore changes in spine kinematics across three different age groups.

View Article and Find Full Text PDF

Lymphatic system failures contribute to cardiovascular and various other diseases. A critical function of the lymphatic vascular system is the active pumping of fluid from the interstitium back into the blood circulation by periodic contractions of lymphatic muscle cells (LMCs) in the vessel walls. As in cardiac pacemaking, these periodic contractions can be interpreted as occurring due to linked pacemaker oscillations in the LMC membrane potential (M-clock) and calcium concentration (C-clock).

View Article and Find Full Text PDF

What is the lower limb length discrepancy after arthroplasty for proximal femoral fracture? A prospective, multicenter observational study of 590 hips.

Orthop Traumatol Surg Res

December 2024

Société Française de Chirurgie Orthopédique et Traumatologique, 56 rue Boissonade, 75014 Paris Cedex, France.

Introduction: Lower limb length discrepancy (LLD) following hip arthroplasty after proximal femoral fracture (PFFA) is little studied. The aim of this work was to answer the following questions: 1) What are the incidence and mean values ​​of LLD after PFFA? 2) What are the clinical consequences (tolerance) of LLD after PFFA? 3) Can we identify risk factors for LLD after PFFA? 4) Is there a significant difference in terms of LLD after PFFA to treat intra- versus extra-capsular fractures?

Hypothesis: LLD after proximal femoral fracture arthroplasty is rare but has good clinical tolerance, given the low functional demands of the patients.

Patients And Methods: This is a multicenter prospective observational cohort study (15 centers), including 590 patients, operated on for hip arthroplasty for proximal femur fracture between May 2022 and June 2023.

View Article and Find Full Text PDF

Residual force enhancement is not altered while force depression is amplified at the cellular level in old age.

J Exp Biol

January 2025

Department of Human Health and Nutritional Sciences, College of Biological Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1.

Residual force enhancement (rFE) and residual force depression (rFD) are history-dependent properties of muscle which refer to increased and decreased isometric force following a lengthening or shortening contraction, respectively. The history dependence of force is greater in older than in younger human adults when assessed at the joint level. However, it is unclear whether this amplification of the history dependence of force in old age is owing to cellular mechanisms or is a consequence of age-related remodelling of muscle architecture.

View Article and Find Full Text PDF

Ultrasound shear wave elastography (SWE) has emerged as a promising non-invasive method for muscle evaluation by assessing the propagation velocity of an induced shear wavefront. In skeletal muscles, the propagation of shear waves is complex, depending not only on the mechanical and acoustic properties of the tissue but also upon its geometry. This study aimed to comprehensively investigate the influence of muscle pennation angle on the shear wave propagation, which is directly related to the shear modulus.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!