Medicine and Health Sciences Commons^™

Molecular Mechanisms Underlying The Muscle Response To Exercise-Induced Muscle Damage In Chronic Cigarette Smokers, Nina Moore

Doctoral Dissertations

Smoking increases risk for musculoskeletal injury and protracts healing. The underlying mechanisms have not been explored, yet dysregulated inflammatory responses may contribute. To investigate these risks, Study 1 of this dissertation monitored typical responses to muscle damaging eccentric contractions (ECC) in smokers and nonsmokers. Smokers experienced greater muscle fatigue both during and immediately after ECC and greater delayed hyperalgesia, a phenomenon known as delayed onset muscle soreness (DOMS), than did non-smokers. DOMS (driven by inflammation) peaks 48h after ECC, when there is a shift from pro- to anti-inflammatory signaling; thus I chose to investigate this time further in smokers. The …

The Role Of The Extracellular Matrix In Mediating Muscle Soreness, Karen L. Riska

Doctoral Dissertations

The goal of this dissertation was to examine the role of the extracellular matrix (ECM) in muscle soreness. Study 1 examined how the disruption of the ECM from a minor surgery (e.g. muscle biopsy) affected muscle soreness. Study 1 showed that soreness levels increased at 24 h post-biopsy compared to baseline and resolved within 96 h. However, the level of muscle soreness at 24 h post-biopsy (20 mm) was lower than that reported for performing a strenuous and naïve exercise (40–80 mm). These results will help review boards at institutions where muscle biopsies are performed understand how a muscle biopsy …

Eccentric Loading Increases Peak Torque Angle Of The Ankle Plantar Flexors In Healthy Volunteers, Matthew Willisch, Peter Hamer, Luke Hopper, Max Bulsara, James R. Debenham

Physiotherapy Papers and Journal Articles

Eccentric loading of the ankle plantar Flexor’s (PF) has demonstrated clinical efficacy in the conservative treatment of Achilles tendinopathy, however, its mechanism of therapeutic benefit remains unclear. The purpose of this study was to examine the effects of PF eccentric loading on PF angle to peak torque (AtPT), peak torque (PT) and lower limb vertical stiffness. Thirty healthy volunteers were randomised to an eccentric (n=15) or concentric (n=13) exercise group. A 10-week loading programme of the ankle plantar flexors was completed. AtPT, PT and vertical stiffness were compared within and between groups before and after the interventions. AtPT increased in …

Eccentric Loading Of Triceps Surae Modulates Stretch Shortening Cycle Behaviour - A Possible Therapeutic Mechanism, J Debenham, W Gibson, M Travers, A Campbell, G Allison

Physiotherapy Papers and Journal Articles

Context: Eccentric exercises are increasingly being used to treat lower limb musculoskeletal conditions such as Achilles tendinopathy. Despite widespread clinical application and documented efficacy, mechanisms underpinning clinical benefit remain unclear. Positive adaptations in motor performance are one potential mechanism.

Objective: To investigate how an eccentric loading intervention influences measures of stretch-shortening cycle (SSC) behaviour during a hopping task.

Design: Within subjects repeated measures observational study.

Setting: University motion analysis laboratory.

Participants: Healthy adults. Interventions: A single intervention of 5 sets of 10 eccentric plantarflexion contractions at 6 RM using a commercial seated calf raise machine.

Main outcome measures: Lower limb …

Eccentric Loading Increases Peak Torque Angle Of The Ankle Plantar Flexors In Healthy Volunteers, Matthew Wellisch, Peter Hamer, Luke Hopper, Max Bulsara, James Debenham

Research outputs 2014 to 2021

Eccentric loading of the ankle plantar Flexor's (PF) has demonstrated clinical efficacy in the conservative treatment of Achilles tendinopathy, however, its mechanism of therapeutic benefit remains unclear. The purpose of this study was to examine the effects of PF eccentric loading on PF angle to peak torque (AtPT), peak torque (PT) and lower limb vertical stiffness. Thirty healthy volunteers were randomised to an eccentric (n=15) or concentric (n=13) exercise group. A 10-week loading programme of the ankle plantar flexors was completed. AtPT, PT and vertical stiffness were compared within and between groups before and after the interventions. AtPT increased in …