Table 4.

Individual studies’ training specifications.

First author, year	Citation number	Type intervention (MCE, Core)	Exercises (No; Name): (Description/Name of exercises)	Type comparator(s)	Training period (weeks)	Training frequency (sessions per week) scheduled, real	Training duration (minutes per session)	Sets (number per exercise)	Repetitions (per set per exercise)	Rest (between sets per exercise; between exercises in seconds)
Alp, 2014	56	Lumbar core stabilization exercise (SE)	N.A	Conventional home-based exercise (HE)	6	SE: 3	45–60 (30 MCE)	SE: N.A HE: 1	SE: N.A HE: 20	N.A., N.A
Alrwaily, 2019	28	Stabilization exercise	5; Abdominal bracing (supine), Abdominal bracing (supine) with heel slide, Abdominal bracing (supine) with leg lifts, Abdominal bracing (supine) with bridging, Bracing with single leg bridging	Stability exercise combined with neuromuscular electrical stimulation	6	2	20	N.A	N.A	N.A.; N.A
Andrusaitis, 2011	60	Stabilization	2: dorsal decubitus, ventral decubitus	Strengthening	7	3	40	1	6—10	N.A.; 30 sec
Arampatzis, 2017	29	Perturbation-based core training	15–18: 3 different perturbation exercises in half-seated position, classical core stability exercises on unstable surfaces	No specific training, normal routine	13	2	90	3	60 sec	180—300; 120
Areeudomwong, 2019	30	Core stabilisation exercise	N.A.: Practiced recruitment of deep trunk muscles, particularly transversus abdominis (TrA) and lumbar multifidus (LM) muscles, together with the diaphragm and pelvic floor muscles, reducing superficial trunk muscle activity in order to improve function of deep trunk muscles and control inter-segmental lumbar spine movement during activities Exercise difficulty was increased by integrating deep muscle cocontraction with controlling movement of extremities and heavier loading positions, such as bridging, bird-dog position and single knee to chest	Proprioceptive Neuromuscular Facilitation Training; Inactive control group	4	3	30	N.A	N.A	N.A.; 60
Bae, 2018	31	Core stability exercises	6: Abdominal drawing-in in 4-point kneeling and supine position, Opposite upper and lower extremity lift in quadruped position, Straight leg raise exercise in prone position, Supine lower extremity extender in supine position, Straight leg raise exercise in supine position, Horizontal side-support exercise in side lying position	Assisted sit-up exercise (SUE)	4	3	30	N.A	N.A	N.A.; N.A
Bauer, 2019	22	Neuromuscular exercise	9; Modified curl up, Bird dog, Side bridge/Mermaid, Single leg stretch, Shoulder bridge, Weight transfer side lunge and one leg stand, “Tai chi warrior”, Lifting up an imaginary Ball, To achieve normal range of motion in thoracic region, and hip and ankle joints,	Inactive control group	24	2	60	N.A	N.A	N.A.; N.A
Brooks, 2012	32	Specific trunk exercise group (SEG)	N.A: Included skilled cognitive activation of the trunk muscles in addition to a number of other best practice exercises: Skilled abdominal contractions and postural training, Side lying trunk exercises (mat-based), Prone lying trunk exercises (mat-based; Hip-specific exercises, Upper and lower limb–focused exercises, Full-body exercises (reformer-based)	Seated cycling	8	3	50–60	N.A	N.A	N.A.; N.A
Chung*, 2018	61	Core stability exercises with flexi bar	4: Abdominal drawing-in maneuver in standing, hook-lying, quadruped, and prone positions by maintaining each motion for 10 s. It was used both hands holding the FB	No further, both groups SE	6	3	30	3	10	180; N.A:
		Core stability exercises	4: Abdominal drawing-in maneuver in standing, hook-lying, quadruped, and prone positions by maintaining each motion for 10 s	No further, both groups SE	6	3	30	3	10	180; N.A:
Critchley, 2007	33	Spinal stabilization (SS)	5: individual transversus abdominis and lumbar multifidus muscle training followed by group exercises that challenged spinal stability	Physio Pain Management	8	8	90	Individual	Individual	individual
Da Luz, 2019	62	Core stability exercise	4; prone bridge, supine bridge, side bridge, bird dog with lower limb elevation As the participants progressed throughout the program, the degree of difficulty of the exercises increased	Core stability exercise combined with neuromuscular electrical stimulation; neuromuscular electrical stimulation only	4	3	N.A	10	N.A	N.A., 60
Demirel, 2019	34	Stabilization exercise	4–5; The TA and multifidus muscles were contracted together with diaphragm respiration appropriately in basic positions (supine, prone, standing, sitting and crawling positions) Progress over the six weeks included different positions, use of resistance bands	Yoga exercises	6	3	60	N.A	N.A	N.A.; N.A
Ferreira, 2007	35	Motor control exercise	N.A.: Improving function of specific trunk muscles thought to control inter-segmental movement of the spine, including transversus abdominis, mul- tifidus, the diaphragm and pelvic floor muscles	General exercise Spinal manipulation therapy	8	12	N.A	N.A	N.A	N.A.; N.A
Franca, 2012	36	Segmental stabilization exercises (SSEs)	4: exercises for the TrA in 4 point kneeling, exercises for the TrA in dorsal decubitus with flexed knees, exercises for the LM in ventral decubitus, Cocontraction of the TrA and LM in the upright position	Stretching (ST)—focused on stretching the erector spinae, hamstrings, and triceps surae	6	2	30	3	15	N.A.; N.A
Ghorbanpour, 2018	57	McGill stabilization exercises group	3: Curl up, Side Bridge, Bird Dog with one hand or one foot and one hand and the opposite leg	Conventional physio (strengthening, stretching, flexibility)	6	3	30	3	10	N.A.; 120
Hosseinifar, 2013	37	Spinal stabalization seercise	N.A	McKenzie Method	6	3	60	10	N.A	N.A.; N.A
Hwang, 2013	71	Sensorimotor training	6: Hollowing exercise, Single leg raising in the quadruped position, contralateral arm and leg raising in the quadruped position, abdominal bracing Holding a bridging position, single leg raising in the bridging position	2 Group: 1 healthy controls ©, 1 lbp physical therapy (C LBP)	4	5	40	N.A	N.A	N.A.; N.A
Ibrahim, 2018	38	Motor control exercise	4–12; Abdominal drawing in in supine, in quadruped, in sitting, in standing, in supine with heel slide, in supine with leg lift (each leg), in supine with bridging, in supine with single-leg bridge, with curl-up, horizontal side support with knees bent, in quadruped with leg raise, etc	Motor control exercise plus patient education; Patient Education only	6	2	30	N.A	10	N.A.; N.A
Inani, 2013	63	Core stability exercies	4: Slow curl ups, sit ups, oblique plank/side bridge, bird dog	Conventional Exercise	12	N.A	N.A	N.A	N.A	N.A.; N.A
Khodadad, 2019	39	Lumbar Stabilization	5; Elbow-Toe, Back Bridge, Hand-Knee, Side Bridge, Curl up	Cognitive functional treatment; Inactive control group	8	3	60	N.A	N.A	N.A.; N.A
Kim, 2018*	40	McGill’s exercise; Sahrmann 0–5 level Exercise	N.A.; curl up, side bridge, and bird dog	No further, both groups SE	8	3	30	N.A	N.A	N.A.; N.A
		Stabilization exercise	N.A.; Pro balance trainer and dynamic air cushion training	No further, both groups SE	8	3	30	N.A	N.A	N.A.; N.A
Kim, 2019	41	Stabilization exercise	4: supine pelvic lift, supine and prone bridging exercise, and side-lying hip abduction	Simulated horseback riding	8	2	30	N.A	N.A	N.A.; N.A
Ko, 2018	64	Lumbar stabilization (LS)	8: sit up, superman, quadruped arm & leg raise, squat, lower body fixation plank, upper body fixation plank, side plank, hip bridge	2 Groups: Sling, Control	12	3	60 min (40 min MCE)	3	10	60; 60
Kofotolis, 2016	42	Pilates	16: Roll down, mermaid, spine stretching, pelvic curl, criss-cross, double leg stretch, hundreds, double knee folds, table top, swimming, swan, catstretch, child’s pose, hips stretch	General strengtheing/stabilisation exercise, control	8	3	60	Progressive: 2 (until week 4), then 3	Progressive: 15 (week 1–2), 20 (w 3–4), 15 (5–6), 20 (7–8)	120; 30
Lee, 2014	65	Ball exercise group	10: exercises on swiss ball from sitting to bridging	PNF pattern group	6	4	N.A	2	20	15; N.A
Lee, 2011	25	Core stability exercises	5: upper body extension in prone position, alternate arm and leg lift in quadruped position, alternate arm and leg lift in prone position, diagonal curl-up and straight curl- up in supine position, quadruped exercises, performed from an all-fours position with the arms and legs extending	Control	4	4	20	N.A	N.A	N.A.; N.A
Letafatkar, 2017	66	SMT-Perturbation with HUBER machine	10: upright stance, push and pull with oscillatory perturbative movements of variable amplitude and speed	Control	5	2	30–45	2–4	2–6	N.A.; 300
Liu, 2019	43	Core Stabilization Exercise on Swiss ball	6: Glute Bridge Pose, Single Leg Bridge, Bridge and Double Knee Flex, Single Leg Bridge and Double Knee Flex, Reverse Bridge, Reverse Bridge and Hip and Knee Flex	Chen-Style Tai Chi	12	3	60	N.A	N.A	N.A.; N.A
Lomond, 2015	58	Trunk stabilization	N.A.: 3 components of spinal stability	Movement System Impairment (MSI)	6	1	45–60	N.A	N.A	N.A.; N.A
Macedo, 2012	44	MCE	N.A	Graded activity	8	2 (4 weeks), 1 (4 weeks)	60	1	10	N.A.; N.A
Marshall, 2013	45	MCE, Pilates	8: Whole body stretching, Skilled abdominal contractions and postural training, side lying trunk, prone lying trunk, hip specific exercises, upper and lower limb, full body exercises, whole body stretching	Stretching and cycling	8	3	55	N.A	N.A	N.A.; N.A
Miller, 2013	24	Stabilzing MCE	10: Phase one: Prone, Supine, Quadruped; Phase two: Supine leg machine, Quadruped -Alternate arm lifts, Alternate leg lifts, standing; Phase three: Quadruped-Alternate arm and leg lifts, Standing with rotation, Bridging	McKenzie	6	N.A	10–15	1	10–50	N.A.; N.A
Moon*, 2013	46	Lumbar stabilization exercises,	16: aimed to strengthen the deep lumbar stabilizing muscles: the transversus abdominis, lumbar multifidi, and internal obliques	No further, both groups SE	8	2	60 (35 min LSE)	1	10	N.A.; 60
		Lumbar dynamic strengthening exercises	14: activated the extensor (erector spinae) and flexor (rectus abdominis) muscle groups	No further, both groups SE	8	2	60 (35 min LDSE)	1	10	N.A.; 60
Noormohammadpour, 2018	47	Multi-step core stability exercise	4: 2 on floor; 2 on swiss ball	Waiting list	8	3		3	10	N.A.; N.A
Rabin, 2014	67	Lumbar stabilization exercise	4: Quadruped, sidelying, supine, and standing positions	Manual therapy	8	Supervised: 2 × first 4 weeks; 1 × week 5–8;	N.A	N.A	N.A	N.A.; N.A
Rasmussen-Barr, 2003	23	Stabilizing training	6–8: motor control, supine crooked-lying, four-point kneeling, prone, sitting and standing	Manual therapy	6	1 supervised, 1 homebased	45 supervised, 10–15 unsupervised	3	15	N.A.; N.A
Rasmussen-Barr, 2009	26	Graded stabilizing exercise	7: supine crooked-lying, four-point kneeling, prone, sitting, standing	30-min walk every day	8	1 supervised, 1 homebased	45 supervised, 10–15 unsupervised	3	15	N.A.; N.A
Rhee, 2012	68	Specific localized exercises aimed at restoring the stabilizing protective function of the spinal muscles around the spinal joint	5: Upper-body extension, alternate arm and leg lift, alternate arm and leg extension on all fours, diagonal curl-up, curl-up	Advice regarding bed rest, absence from work, prescription medications, and resuming normal activity as tolerated	4	5	N.A	N.A	N.A	N.A.; N.A
Salamat*, 2017	48	Movement control	N.A.: The aim of the intervention was to normalize the abnormal movement patterns and postures and to relax trunk muscles. Exercises involved training to modify pain provocative postures and movement patterns in order to decrease pain while performing the task	No further, both groups SE	4	2	45	3	15–30	60 – 120; 300
		Stabilization exercise	N.A.: Exercises involved coordinated training and independent activity of deep trunk muscles including transversus abdominis and multifidus in pain-free positions and movements	No further, both groups SE	4	2	45	3	15–30	60 – 120; 300
Seo, 2019	49	Trunk stability exercise	16: nine movements of mat-based trunk stability exercises and seven movements of Swiss ball trunk stability exercises	Gyrotonic exercise	4	3	N.A:	N.A	N.A	N.A.; N.A
Shamsi*, 2017	50	MCE	N.A.: Progressive classic stabilization	No further, both groups SE	6	3	20	N.A	10	N.A.; N.A
		Core	N.A.: Exercises were performed in a lying position starting with simple movements and advancing to more difficult exercises (e.g. on a Swiss ball)	No further, both groups SE	6	3	20	N.A	10	N.A.; N.A
Shaughnessy, 2004	51	Core	3: Prone lying, kneeling, supine	Standard physiotherapy	10	2 (week 1–2), 1 (week 3–10)	60 week 1, else 30	N.A	Max. 10	N.A.; N.A
Soundararajan, 2016	59	Multifidus muscle retraining	8: Bridging, lying prone, quadruple, prone lying, leg extension, sitting, standing, shoulder flexion	Traditional back exercises (strength and stretching)	6	3	20	1	20	N.A.; 120–240
Sung, 2013	27	Core	5: Knee to chest for each leg in supine position, double leg knee to chest in supine position, prayer stretch on all fours, leaning forward position while sitting, lateral side stretch in standing position	Flexibility	4	1 supervised, 6 homebased	20	2	15	N.A.; N.A
Ulger, 2017	52	Stabilization	N.A: Increasing intensity and changing exercises once/week	Manipulation	6	3	60	3	10	N.A.; N.A
Unsgaard-Tondel, 2010	53	Sling	N.A: Sling	Low-load MCE (feedback) and General exercise	8	1	40	N.A	N.A	N.A.; N.A
Vikranth, 2015	69	Core stabilization	8: Week 1: Transversus abdominus activation, transversus abdominus marching, pelvic tilt, segmental bridge; Week 2: Fall out, modified crunch, cat stretch, back extension	MCE (passive)	2	5	35		Week 1: 8; week 2: 15	120; N.A
Waseem, 2018	54	Core stabilization	7: Pressure feedback core exercise, multifidus exercise, frontal and side plank exercise, pelvic floor exercises, diaphragmatic strengthening, single leg standing on foam, tandem standing with perturbation	Routine exercise	6	1 supervised, 2 homebased	N.A	N.A	N.A	N.A.; N.A
Woo*, 2016	55	Lumbar stabilization exercise	6: Lower extremity lifting in a bridge posture, lower extremity lift in a prone position on a ball, upper extremity lift in a prone position on a ball, moving the body forward grasping a sling in a kneeling position, lifting the buttocks with the lower extremity hooked on a sling in a supine position;	No further, both groups SE	4	N.A	40 (30 min MCE)	Group A: 4 Group B: 2	10–12	N.A.; N.A
		Lumbar stabilization exercise with thoracic extension exercise	10: Lower extremity lifting in a bridge posture, lower extremity lift in a prone position on a ball, upper extremity lift in a prone position on a ball, moving the body forward grasping a sling in a kneeling position, lifting the buttocks with the lower extremity hooked on a sling in a supine position; plus thoracic extension exercise	No further, both groups SE	4	N.A	40 (30 min MCE)	Group A: 4 Group B: 2	10–12	N.A.; N.A
Young, 2015	70	Swiss ball stabilization	N.A	PNF	6	3	50	N.A	N.A	N.A.; N.A

All interventions and the respective comparators are described. exercises, stabilisation exercise; N.A., not applicable.

*Both groups were included into quantitative analysis (meta-regression).