Table 1.

Main characteristics of included studies

First author, year, country [reference]	Study design	Subjects	Intervention	Type of supervision	Primary outcomes
Hand exercises
Piga, 2014, Italy [44]	RCT	E: n = 10, mean age=57.0 years, mean disease duration = 6.9 years, female n = 10, diffuse/limited subtype 2:8 C: n = 10, mean age = 57.4 years, mean disease duration = 6.7 years, female n = 10, diffuse/limited subtype 2:8	Strengthening and mobility hand exercises done at home using the Re.Mo.Te device; 50 min, 5 days/week for 12 weeks C: exercises using common daily-life objects	Every patient received individual 1 h training on the use of the device, along with an illustrated booklet describing the exercises. Every workout was remotely monitored by physicians through the telemonitoring interface	Hand function measured by HAQ, functional index for hand OA and the hand mobility in scleroderma test
Landim, 2017, Brazil [41]	OD	n = 22, mean age = 48.09 years, mean disease duration = 11.19 years, female n = 18, diffuse/limited subtype 6:16	Home-based self-management programme consisting of hand exercises and concise instructions about SSc	Instructions in the program	Hand pain (visual analog scale) and hand function (Cochin hand function scale)
Orofacial exercises
Yuen, 2011, USA [13]	RCT	E: n = 13, mean age = 51.8 years, mean disease duration = 11.3 years, female N = 11, diffuse/limited subtype 8:5, mean oral aperture = 27.4 mm C: n= 15, mean age = 50.9 years, mean disease duration = 6.2 years, female n = 11, mean, diffuse/limited subtype 6:9, mean oral aperture = 32.4 mm	Manual mouth-stretching and oral-augmentation exercises; 6 min, twice daily for 26 weeks C: no exercise	Patients were taught to perform manual mouth-stretching and oral augmentation exercises by a trained research coordinator. Handouts with pictures showing the exercises were given	Oral aperture
Pizzo, 2003, Italy [11]	OD	n = 10, mean age = 56.8 years, female n = 10, mean maximal mouth opening = 26 mm	Mouth-stretching exercises and oral augmentation exercises, 20 minutes, twice daily for 18 weeks	Patients were instructed by one of the investigators to perform the exercise programme	Maximal mouth opening
Aerobic and muscle-strengthening exercises
Mitropoulos, 2018, UK [42]	RCT	E1: n = 11, mean age = 69.1 years, mean disease duration = 7.8 years, limited subtype E2: n = 11, mean age = 65.1 years, mean disease duration = 7.7 years, limited subtype C: N = 12, mean age = 62.2 years, mean disease duration = 6.3 years, limited subtype	E: 2 days/week for 12 weeks, 30 min of 30 s high-intensity-interval training followed by 30 s passive recovery. In the E1 group this was performed on an arm-crank ergometer and in the E2 group on a cycle ergometer C: no exercise	Supervised sessions at sport venues of the hospital	VO2peak EQ-5D-5-L 6 min walking testa
Mitropoulos, 2019, UK [43]	RCT	E: n = 16, mean age = 69.6 years, mean disease duration = 8 years, limited subtype C: n = 16, mean age=63.6 years, mean disease duration=8 years, limited subtype	E: exercise programme consisting of: (a) high-intensity interval training; and (b) resistance training (five upper body exercises in a circuit row for three circles interspersed by 2–3 min), 2 days/week for 12 weeks C: no exercise	Supervised sessions at sport venues of the hospital	VO2peaka
Oliveira, 2009, Brazil [23]	OD	E: n = 7, mean age = 45.6 years, mean disease duration = 12.6 years, female n = 7, diffuse/limited subtype 2: 5, mean forced vital capacity for diffuse subtype = 77.5% of predicted and for limited subtype 103.8% of predicted	Aerobic exercise (30 min of treadmill walking at moderate intensity), 40 min, 2 days/week for 8 weeks	Supervised sessions	VO2peak, oxygen saturationa
Pinto, 2011, Brazil [12]	OD	n = 11, mean age = 44.0 years, mean disease duration = 7.36 years, female n = 11, diffuse/limited subtype 8:3	Aerobic training (20 min of treadmill exercise at a heart rate of ∼70% of VO2peak), resistance training (30 min, four sets of 8–12 maximal repetitions for the main muscle groups), 2 days/week for 12 weeks	Supervised training	Oxygen uptake, highest exercise load for bench and leg pressa
Alexanderson, 2014, Sweden [27]	Single subject experimental design	n = 4, mean age = 66.5 years, mean disease duration = 3.5 years, female N = 3, lung fibrosis with 50–80% forced vital capacity/100% forced vital capacity = 2:2	Aerobic exercise (ergometer cycling of maximum 30 min. Intensity increased from light exertion to 15 on a Borg scale) and muscular endurance training for shoulder and hip flexors, 30–50 min, 3 days/week for 8 weeks	Supervised by a trained physical therapist	6 min walking test

^aFor these studies the primary outcomes were not defined in the text, but we chose the main outcomes based on our definition of physical functioning outcomes in the text.

C: control group; E: experimental group; OD: observational design; RCT: randomized controlled trial; VO₂peak: peak oxygen consumption.