None listed
Conditions
Brief summary
The primary aim of this acute study is to examine the acute effects of resistance exercise performed with ISR compared to TRAD on the maintenance of force, velocity, and power output, as well as differences between exercises targeting the upper and lower limbs in adults with CMT. Secondary aims include whether better affective responses and less physiological and psychological fatigue can be achieved following resistance exercise using ISR compared to TRAD sets. Hypotheses: 1. Resistance exercise performed with ISR will lead to higher mean force, velocity, and power output across the set compared to resistance exercise performed with TRAD. 2. Resistance exercise performed with ISR will lead to lower perceived effort and more positive and less negative affective responses compared to resistance exercise performed with TRAD. 3. Resistance exercise performed with ISR will lead to greater muscle oxygenation and blood flow compared to resistance exercise performed with TRAD. 4. Muscle oxygenation and blood flow will explain a significant portion of the variance in power output, velocity, perceived effort, and affective responses between groups. 5. Similar responses for upper versus lower limb resistance exercises will be observed following the ISR and TRAD conditions.
Interventions
The experimental session will be conducted in an exercise clinic at the University of Sydney Camperdown campus (Susan Wakil Health Building). Specifically, the experimental sessions will involve a 5-minute warm-up followed by 30 minutes spent performing the exercises (inclusive of resistance exercise and recovery times). All sessions will be supervised by an exercise physiologist or exercise scientist with one-on-one supervision provided to participants. There will be 7 days between the two experimental sessions (i.e., wash-out). Familiarisation will be conducted at end of an initial testing visit and will involve performing 2 sets of the chest press and the leg press following the exercise prescription used for the ISR condition (details described below). The intra-set recovery (ISR) condition will involve 4 sets of 2 clusters of 5 repetitions at 70% one-repetition maximum (1RM) with 30 seconds of rest between clusters and 90 seconds of rest between sets. Participants will perform the chest press prior to the leg press (in this order). The warm-up during experimental sessions will involve completing 1 set of 8 repetitions for the exercises performed in the session (i.e., chest press or leg press) with a load equivalent to 40% of 1RM. After 2 minutes of rest following the warm-up, participants will commence the first set of the experimental condition. The Keiser A420 pneumatic (air resistance) equipment (Fresno, CA, USA) will be used for the chest press and leg press. Participants will be instructed to refrain from moderate-vigorous exercise and any activities outside of daily living for the previous 72 hours prior to each session. Participants will also be asked not to start any other new exercise regimen or intentionally change their habitual diet throughout the entire study and assessment.
Sponsors
Study design
Eligibility
Inclusion criteria
To be included in this study individuals need to be clinically diagnosed with Charcot-Marie-Tooth disease (CMT) based on genetic and electrophysiological data. Participants need to be free of rotator cuff tear or history of any shoulder or back or lower extremity condition, injuries, surgeries, congenital malformations, back, knee, or hip osteoarthritis, recent fracture (12 months), cognitive impairment as defined by Montreal Cognitive Assessment score of 27-30, acute or terminal illness and any unstable or ongoing cardiovascular/respiratory disorders.
Exclusion criteria
Individuals with morbid obesity (BMI > 40) will also be excluded since thick subcutaneous fat might impair NIRS outcomes. Participants that cannot speak English. People will be excluded if they are not sufficiently ambulatory (defined as the inability to walk 100 m in under 4 minutes).