Table 1.

Characteristics of the included studies.

	Participants (E/C)	Eccentric Exercise Group	Comparison Group	Outcome Measures
Eccentric exercise + adjuvant treatment vs. adjuvant treatment
Anitha and Prachi (2018) [36]	N = 30/30 Age (y), NR/NR Sex (M/F), NR/NR Duration (mo), NR/NR	Eccentric exercise + Standardized conventional therapy Device: Rubber bar 3 sets of 15 repetitions 6 session/week Duration, 2 weeks	Standardized conventional therapy (pulsed ultrasonic therapy)	Pain: Numerical pain rating scale (0–10) Grip strength (maximum)
Croisier et al. (2007) [37]	N = 46/46 Age (y), 40 (SD, 8)/38 (SD, 8) Sex (M/F), 36/56 Duration (mo), 8 (SD, 4)/8 (SD, 3)	Isokinetic eccentric exercise + Non-strengthening rehabilitation Device: Cybex Norrn dynamometer 2 sets of 10 repetitions for wrist extensors and forearm supinators 3 times/week Duration, 9 weeks	Non-strengthening rehabilitation (e.g., ultrasound, analgesic TENS, ice, deep friction massage, and stretching)	Pain: VAS score (0–10) Eccentric muscle strength Disability questionnaire
Martinez-Silvestrini et al. (2005) [38]	N = 31/33 Age (y), 46.6 (SD, NR)/43.1 (SD, NR) Sex (M/F), NR/NR Duration (mo), NR/NR	Eccentric exercise + Self-applied ice massage and stretching of wrist extensors Device: Elastic resistance band 3 sets of 10 repetitions Daily Duration, 6 weeks	Self-applied ice massage and stretching of wrist extensors	Pain: VAS score (0–100) Grip strength (pain-free) DASH PRFEQ SF-36
Soderberg et al. (2012) [40]	N = 20/22 Age (y), 48 (SD, 12.4)/50 (SD, 10.8) Sex (M/F), 24/18 Duration (mo), NR/NR	Eccentric exercise + Forearm band and warm-up exercise Device: Bucket 2→3 sets of 8–12 repetitions Daily → Twice a day Duration, 6 weeks	Forearm band and warm-up exercise for wrist extensors (flexion, extension, abduction, adduction and circumduction for 1 min twice a day)	Pain: VAS score (0–100) Grip strength (pain-free)
Eccentric exercise vs. Other exercises (concentric or isotonic)
Martinez-Silvestrini et al. (2005) [38]	N = 31/30 Age (y), 46.6 (SD, NR)/47.0 (SD, NR) Sex (M/F), NR/NR Duration (mo), NR/NR	Eccentric exercise + Self-applied ice massage and stretching of wrist extensors Device: Elastic resistance band 3 sets of 10 repetitions Daily Duration, 6 weeks	Concentric exercise + Self-applied ice massage and stretching of wrist extensors Same protocol with eccentric exercise	Pain: VAS score (0–100) Grip strength (pain-free) DASH PRFEQ SF-36 results
Peterson et al. (2014) [39]	N = 60/60 Age (y), 48.8 (SD, 6.7)/47.0 (SD, 9.4) Sex (M/F), 63/57 Duration (mo), NR/NR	Eccentric exercise Device: Dumbbell (using a specified amount of water in a plastic container) 3 sets of 15 repetitions DailyDuration, 3 months	Concentric exercise Same protocol with eccentric exercise	Pain: VAS score (0–100) Forearm extensor muscles strength DASH Gothenburg Quality of Life instrument questionnaire
Tyler et al. (2010) [41]	N = 11/10 Age (y), 47 (SD, 2)/51 (SD, 4) Sex (M/F), 10/11 Duration (wk), 6 (SD, 2)/8 (SD, 3)	Eccentric exercise + Wrist extensor stretching, ultrasound, cross-friction massage, heat, and ice Device: Rubber bar 3 sets of 15 repetitions Daily Duration, 7 weeks	Isotonic exercise + Wrist extensor stretching, ultrasound, cross-friction massage, heat, and ice	Pain: VAS score (0–10) DASH

E, experimental; C, comparison; M, male; F, female; SD, standard deviation; NR, not reported; VAS, visual analog scale; DASH, disabilities of the arm, shoulder, and hand; PRFEQ, patient-rated forearm evaluation questionnaire SF-36, short form-36.