2. Characteristics of exercise interventions for ARI.

Study ID	Location	Type of exercise	Setting/frequency	Intensity	Duration	Supervision	Comparison group	Outcomes in meta‐analysis
Barrett 2012	USA	Bicycle, treadmill, and brisk walk	UW Health Sports Medicine Center 1 group contact (2.5 hours per week) + 45 minutes home practice per day	12 to 16 Borg Scale	8 weeks	Supervised by exercise physiologist	Meditation and non‐exercise	Number of ARI episodes, proportion of people with ARI, ARI severity, number of symptoms per day, laboratory parameters ‐ neutrophils, quality of life, cost to patient, adherence to intervention
Barrett 2018	USA	Bicycle, treadmill, and brisk walk	UW Health Sports Medicine Center 1 group contact (2.5 hours per week) + 45 minutes home practice per day	12 to 16 Borg Scale	8 weeks	Supervised by experienced exercise instructors	Non‐exercise	Number of ARI episodes, proportion of people with ARI, ARI severity, number of symptom days, laboratory parameters ‐ neutrophils, quality of life, cost to patient, adherence to intervention
Chubak 2006	USA	Bicycle, treadmill, or walk	Study facilities 5 days per week; plus 2 days per week at home	45 minutes of moderate‐intensity exercise	12 months	Supervised by exercise physiologist in the first 3 months	Once‐weekly, 45‐minute stretching sessions	Adherence; ARI episodes
Ciloğlu 2005	Turkey	Walking on a treadmill or an outdoor track	Indoor and outdoor exercises at university 5 days per week	30 minutes each time respectively at 60% MHR	12 weeks	Supervised	Outdoor exercise and non‐exercise	Adherence; ARI symptoms
Dias 2014	Brazil	Resistance training	Gymnasium, group exercise, 3 days per week	Each weight was determined subjectively.	9 weeks	Supervised training	Non‐exercise	Adherence
Klentrou 2002	Canada	Bicycles, treadmills, stair climbers, or combined	Research centre, group exercise, 3 days per week	30 minutes at 75% HR reserve + 15 minutes of stretching	12 weeks	Supervised	Non‐exercise	Adherence; ARI symptoms; salivary secretion immunoglobulin
Manzaneque 2004	Spain	Qigong (traditional Chinese exercise)	Research centre, group exercise, 5 days per week	8 distinct movements repeated 8 times for 30 minutes each session	4 weeks	Qualified Qigong instructor	Non‐exercise	Adherence
Nieman 1990	USA	Walking	Research centre, group exercise, 5 days per week	45 minutes at 60% reserve heart rate	15 weeks	Supervised	Non‐exercise	Adherence; ARI episodes; ARI symptoms; lymphocytes
Nieman 1993	USA	Brisk walking	Research centre, group activity, 5 days per week	30 to 40 minutes at 60% target heart rate	12 weeks	Supervised	Calisthenics	Adherence; ARI episodes; lymphocytes
Nieman 1997	USA	Walking	Research centre, indoor group activity, 5 days per week	45 minutes at 60% to 80% reserve heart rate	12 weeks	Supervised	Non‐exercise	Adherence; ARI symptoms; lymphocytes
Silva 2018	Portugal	Resistance training and aerobic training	Research centre, indoor group activity, 3 days per week	90 min (10 min of warm‐up, 30 min of aerobic training, and 45 min of resistance training, ending with a 5‐minute cool‐down)	36 weeks	Supervised training by physical education	Non‐exercise	Number of ARI episodes, proportion of people with ARI, severity of ARI, number of symptoms days per episode, adherence to intervention group
Sloan 2013	USA	Walking	Home‐based exercise 5 days per week	30 minutes at 75% of individual HR max	16 weeks	Not supervised	Non‐exercise	ARI episodes; adherence; ARI symptoms; salivary secretion immunoglobulin
Weidner 1998	USA	Bicycle, walking, or jogging	Research centre, group activity, 6 days of exercise	30 minutes at 70% of target heart rate	10 days	Supervised training	Non‐exercise	Adherence; ARI symptoms
Weidner 2003	USA	Bicycle, walking, or jogging	Research centre, group activity, 5 days per week	30 minutes at 70% of target heart rate	7 days	Supervised	Non‐exercise	Adherence

ARI: Acute Respiratory Infection
 HR: Heart Rate
 MHR: Maximal Heart Rate