Table 1.

Characteristics of included studies (n = 17).

Year, title	Participants	Age	Duration	Intervention	Comparator	Assessment	Outcomes	Follow-up	Financial support
Chok, 1999	Sex Male and Female Classification Subacute Radiation With or without	Exercise Mean: 37.5 SD: 9.7 Control Mean:34.2 SD: 8.1	6 weeks (3 times a week)	Exercise (n = 30) 4 Levels of shoulder lift exercises (30–45 min)	No intervention (n = 24) Postural and back care advice and the back-care booklet	Sorensen test (s)	↔ Endurance of trunk extensors	No	No information available
Mannion, 2001*	Sex Male and Female Classification Chronic Radiation Without	Age Mean: 45.0 SD: 10.0	12 weeks (2 times a week)	Training devices (n = 41) 3 planes Submaximal isoinertial—25 repetitions/session on each device—1 h	Physiotherapy + home exercises (n = 46) Isometric and therabands—30 min Aerobic/stretching (n = 45)—1 h	Sorensen test (s) Electromyogram (Hz)	↑ Isometric strength < devices group ↑ Activation of the erector spinae extension ↑ Endurance	No	No information available
Rittweger, 2002	Sex Male and Female Classification Chronic Radiation Without	Isodynamic Mean: 49.8 SD: 6.6 Vibration Mean: 54.1 SD: 3.4	12 weeks (1 or 2 times a week)	Isodynamic lumbar extension exercise (n = 25) Resistance exercise of the abdominal and thigh muscles	Whole-body vibration exercise (n = 25) A platform that oscillates between the subject’s feet	LE Mark1 Lumbar extension machine (Nm/kg)	↑Lumbar extension torque < Isodynamic lumbar extension exercise group	6 months	No information available
Maul, 2005	Sex Male and Female Classification Chronic Radiation Without	Exercise Mean: 38 SD: 8 Comparison Mean: 39 SD: 10	Exercise: 12 weeks (2 times a week) Comparison: 3 sessions	Exercise group strengthening exercises + back school (n = 74) Static and dynamic exercises with small weights, machines	Comparison Low Back School (n = 74) Informational classes	Sorensen test (modified) (s) Isokinetic dynamometer (Nm)	Both groups < in the exercise group: ↑ Muscular endurance ↑Isokinetic strength	1 year and 10 years	No information available
Harts, 2008*	Sex Male Classification Chronic Radiation With or without	HIT Mean: 44 SD: 10 LIT Mean: 42 SD: 10 Control Mean: 41 SD: 9	8 weeks (1 to 2 times a week)	High-intensity training- HIT (n = 20) 1 Progressive resistance exercise program for the isolated lumbar extensor muscles	Low-intensity training (n = 19) One non-progressive, low-intensity resistance No intervention Control (n = 21) Waiting list	Modified lower back machine (Nm)	↑Isometric back strength  ↔ Between HIT and LIT	24 weeks	No information available
Kell, 2009*	Sex Nod reported Classification Chronic Radiation Without	Resistance Mean: 40.1 SD: 8.7 Aerobic Mean: 36.7 SD: 8.9 Control Mean: 35.3 SD: 7.3	16 weeks (3 times a week)	Resistance exercises (n = 9) 12 Upper-and lower-body RT exercises that consisted of free weights, machines, and body weight	Aerobic training (n = 9) elliptical and treadmill No intervention control (n = 9)	Sorensen test 10RM testing	Resistance group: ↑Musculoskeletal fitness	No	Yes
Macedo, 2010	Sex Female Classification Chronic Radiation Without	Isostretching. group Mean: 21.11 SD: 2.02 Control Mean: 20.6 SD: 0.81	20 sessions (3 times a week)	Isostretching (n = 9) 9 Isometric contractions of glutes, quadriceps, abdominals, and pelvic floor	No intervention control (n = 6)	Test of maximum repetition in one minute (RM)	Isostretching: ↑ Muscular resistance abdominals, gluteus maximus, and trunk extensors	No	No information available
Bronfort, 2011	Sex Male and Female Classification Subacute Radiation with or without	Supervised Mean:44.5 SD: 11.8 Home Mean: 45.6 SD: 10.3 Chiropractic Mean: 45.2 SD: 10.8	12 weeks (2 times a week)	Supervised Exercise Therapy (n = 100) Seven exercises focused on the low back and abdominal musculature + core strengthening	Home exercise (n = 101) Three strengthening + advice and stretching Chiropractic Spinal Manipulation (n = 100) low back and sacroiliac	Sorensen test Lumbar dynamic motion (Orthopedic Systems)	Supervised > Chiropractic and Home exercise: ↑ Muscle endurance ↑ Strength	52 weeks	No information available
Smith, 2011	Sex Not reported Classification Chronic Radiation Without	Age Mean: 42.93 SD: 10.80	12 weeks (1 time a week)	Lumbar extension training with pelvic stabilization (STAB) (n = 15)	Lumbar extension training without stabilization (n = 15) No intervention (n = 12)	Lumbar Extension Machine (Nm)	STAB group: ↑ Lumbar strength at all joint angles	No	No information available
França, 2012	Sex Not reported Classification Chronic Radiation Not reported	Stretching Mean: 41.53 SD: 4.41 Seg. Stab. Mean: 42.07 SD: 8.15	Six weeks (2 times a week)	Stretching (n = 15) 4 Exercises focused on stretching the erector spinae, hamstrings, and triceps surae	Segmental stabilization (n = 15) 4 Exercises focused on the TrA and lumbar multifidus muscles	Pressure Biofeedback Unit (mmHg)	Both treatments: ↑ Transversus Abdominis Activation Capacity	No	No information available
Bruce-Low, 2012*	Sex Not reported Classification Chronic Radiation Without	Age Mean: 45.5 SD: 14.1	12 weeks (2 or 1 time a week)	Exercise (n = 20) (twice a week) 1 Lumbar extension machine 8–12 rep—80% of the maximum TFT	Exercise (once a week) (n = 31) 1 Lumbar extension machine No intervention (n = 21)	Lumbar extension machine (Dynamometer) (Nm)	Both training: ↑ Maximal strength ↑ Range of motion and	No	No information available
Alp, 2014	Sex Female Classification Chronic Radiation Without	Core exercise Mean: 48 SD: 33.74 Home-based Mean: 51 SD: 48.73	6 weeks (3 times a week)	Core stabilization exercise (n = 24) 4 Stretching, stabilization exercises for the multifidus/ transversus abdominis muscles	Home-based exercise (n = 24) 2 Lumbar isometric and lumbar flexion–extension exercises 20 rep	Sorensen test (s) Kraus-Weber test (sec)	Both treatments: ↑ Endurance abdominal muscles and dorsal extensors	No	No financial support
You, 2015	Sex Not reported Classification Chronic Radiation Without	Training Mean: 27.6 SD: 5.6 Control Mean: 27.6 SD: 6.7	6 weeks (2 times a week)	Training group: Exercise (n = 7) 6 Stabilization exercise using a S.E.T system	No intervention (n = 5)	Muscular strength dynamometer (kg-m / BW)	Training group: ↑Muscular strength ↑Endurance	No	Yes
Lomond, 2015	Sex Male and female Classification Chronic Radiation Without	Stabilization Mean: 43.1 SD: 11.9 Control Mean: 41.6 SD: 10.9	7 weeks	Trunk stabilization (n = 12) Motor control, strengthening, submaximal efforts STB and an education booklet	Movement system impairment (n = 21) Education booklet	Electromyogram (Hz)	APA characteristics (i.e., force application or EMG amplitude)	12 months	Yes
Knox, 2017	Sex Male and female Classification Chronic Radiation Without	Exercise Mean: 33.9 SD: 1.9 Control Mean: 34.6 SD: 2.2	8 weeks (3 times a week)	Exercise (n = 12) Pilates, 3 exercise sessions	No intervention control (n = 12)	Electromyogram (Hz)	↑ Ipsilateral transverse abdominis/internal oblique ↑Control of rotational torques	No	No information available
Cortell-Tormo, 2018*	Sex Female Classification Chronic Radiation Without	Exercise Mean: 35.6 SD: 7.9 Control Mean:35.6 SD: 9.7	12 weeks (2 times a week)	Exercise (n = 11) 18 Upper and lower body resistance training exercise—free weights, gym and body weight	No intervention control (n = 8)	Balance (trials to 60 s); Curl-up (rep); Squat (rep); Static back (s); Side bridge(s)	↑ Physical function ↑ Balance ↑ Squat ↑ Static back ↑ Side Bridge	No	Yes
Bello, 2018*	Sex Male and Female Classification Chronic Radiation Without	Stab. group Mean:42.2 SD: 12.91 Treadmill Mean: 46.6 SD: 11.6	8 weeks (3 times a week)	Stabilization exercises (n = 25) 4 exercises—McGil protocol	Treadmill walking exercise (n = 25) Modified Bruce protocol	Electromyogram (Hz)	↑ Multifidus muscle activation < Stabilization exercises	No	No information available

HIT high-intensity training, LIT low-intensity training, TrA transversus abdominis.

*Studies included in the meta-analysis.

 ↔ No significant difference, ↑ Significant Increase, ↓ Significant Decrease, < Significantly more.