title: Effects of warm-up on hamstring muscles stiffness: Cycling vs foam rolling.
abstract: This study investigated the effects of active and/or passive warm-up tasks on the hamstring muscles stiffness through elastography and passive torque measurements. On separate occasions, fourteen males randomly completed four warm-up protocols comprising Control, Cycling, Foam rolling, or Cycling plus Foam rolling (Mixed). The stiffness of the hamstring muscles was assessed through shear wave elastography, along with the passive torque-angle relationship and maximal range of motion (ROM) before, 5, and 30 minutes after each experimental condition. At 5 minutes, Cycling and Mixed decreased shear modulus (-10.3% ± 5.9% and -7.7% ± 8.4%, respectively; P≤.0003, effect size [ES]≥0.24) and passive torque (-7.17% ± 8.6% and -6.2% ± 7.5%, respectively; P≤.051, ES≥0.28), and increased ROM (+2.9% ± 2.9% and +3.2% ± 3.5%, respectively; P≤.001, ES≥0.30); 30 minutes following Mixed, shear modulus (P=.001, ES=0.21) and passive torque (P≤.068, ES≥0.2) were still slightly decreased, while ROM increased (P=.046, ES=0.24). Foam rolling induced "small" immediate short-term decreases in shear modulus (-5.4% ± 5.7% at 5 minutes; P=.05, ES=0.21), without meaningful changes in passive torque or ROM at any time point (P≥.12, ES≤0.23). These results suggest that the combined warm-up elicited no acute superior effects on muscle stiffness compared with cycling, providing evidence for the key role of active warm-up to reduce muscle stiffness. The time between warm-up and competition should be considered when optimizing the effects on muscle stiffness.
authors.affiliation: Laboratory "Sport, Expertise and Performance" (EA 7370), Research Department, French Institute of Sport (INSEP), Paris, France.|Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain.
authors.forename: A J
authors.initials: AJ
authors.lastname: Morales-Artacho
authors.affiliation: Laboratory "Sport, Expertise and Performance" (EA 7370), Research Department, French Institute of Sport (INSEP), Paris, France.|Laboratory "Movement, Interactions, Performance" (EA 4334), Faculty of Sport Sciences, University of Nantes, Nantes, France.
authors.forename: L
authors.initials: L
authors.lastname: Lacourpaille
authors.affiliation: Laboratory "Sport, Expertise and Performance" (EA 7370), Research Department, French Institute of Sport (INSEP), Paris, France.
authors.forename: G
authors.initials: G
authors.lastname: Guilhem
mesh_terms: D000328:Adult; D001642:Bicycling; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques; D004576:Electromyography; D000070633:Hamstring Muscles / Q000502:physiology* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008405:Massage; D016059:Range of Motion, Articular; D019415:Torque; D063996:Warm-Up Exercise; D055815:Young Adult
keywords: active warm-up; elastography; passive torque; passive warm-up; risk of muscle injuries