Exercise Training on Health Outcomes in Scleroderma (ETHOS) Trial

This study will be investigating the efficacy of a 12-week supervised and personalised graded exercise training program in attenuating functional decline and improving health outcomes in systemic sclerosis (SSc) patients. The goal-directed exercise training program will consist of 30-60 minutes of supervised, aerobic and resistance training performed three times per week. Two sessions will be performed in-person in a gym-based setting, and one session will be performed remotely over telehealth. A multi-component exercise approach will be utilised to target the diverse pathophysiological processes that contribute to symptoms of exertional intolerance in individuals with SSc. This will include high-intensity interval training, moderate intensity continuous training, functional circuit training and progressive moderate-to-high intensity resistance training. The exercise prescription will be individualised to each participant's cardiopulmonary exercise test and muscle function assessments as well as their health and disease-specific factors. Exercise sessions will be prescribed and overseen by an Accredited Exercise Physiologist (AEP) and all training supervised by an appropriately trained AEP and/or Exercise Scientist. The program will consist of one week of familiarisation, and then two 5-week blocks incorporating a progressive increase in exercise duration and/or intensity (i.e progressive overload), which is followed by a de-load/recovery week. Session attendance will be logged and reminders sent out at least at least 24 hours prior to sessions. Aerobic Training Sessions: The aerobic component will consist of one continuous steady-state and two interval training session a week with all the sessions being completed on an upright cycle ergometer, with monitoring by the 1-10 rate of perceived exertion (RPE) for dyspnoea, and RPE 6-20 for effort, and/or smartwatches (with heart rate monitoring). For the telehealth session, participants will either use their own equipment (treadmill or cycle ergometer) or will work with the AEP to develop a moderate-intensity aerobic session that the participant can perform independently based on their goals and preferences such as walking outside. All sessions will include a 5-minute light-intensity aerobic warm-up and cool-down. The steady-state sessions will be completed from home with remote supervision via telehealth and will consist of 20-60 minutes of continuous cycling (not including the warm-up or cool-down) at a moderate intensity. The target heart rate for steady state sessions will be set at 5-15 beats/min below the heart rate corresponding to the ventilatory threshold or an RPE for effort of 12-14. The interval sessions will be performed in-person on a cycle ergometer or elliptical trainer, and will consist of 8-20 x alternating work intervals of 30-60 seconds at 80-100% of peak power output from the cardiopulmonary exercise test (CPET), interspersed with 30-90 seconds of unloaded cycling for recovery, and a longer recovery bout incorporated after every 4-5 intervals as required. Resistance Training Sessions: As part of the supervised training sessions, participants will complete six compound resistance exercises (three upper-body and three lower-body exercises) which will be centred around functional strength and endurance. Up to 3 sets of up to 15 repetitions will be utilised in the program which will include standard resistance exercises such as leg press, squats, lunges, step-ups, seated rows, chest-press, overhead shoulder press and lat pull-down. Exercise modifications will be made to accommodate participants with limited hand-grip strength and other mobility limitations. In the first 5-weeks of the program, participants will perform 1-3 sets of 12-15 repetitions that can be lifted before fatigue, along with a de-load/recovery week consisting of 1 set of each exercise. As part of the second 5-week block, participants will complete 2-3 sets of 6-12 repetitions until fatigue. Participants will be allowed to rest for 1-2 minutes between each set of exercise. Participants will be monitored using RPE scales, oxygen saturation, and HR throughout the session. The exercises performed in weeks 1-6 will be modified or changed slightly for weeks 7-12 for variety and progression purposes. For the home-based telehealth session, participants will instead perform a personalised circuit resistance session using exercises based on functional daily tasks such as sit-to-stand, incline push-ups, three-point rows and will consist of minimal equipment (mainly bodyweight and resistance bands).