Table 2.

Description of core physical fitness exercises assessed in the included studies.

Curl-Up or Crunch	Participant is in a supine position with feet on the floor (hip-width apart) and knee flexion. Upper body is lifted with hands behind the neck and then returned to the starting position. This exercise may vary depending on specific protocols (e.g., arms placed across the chest, 90° hip and knees flexion, curl-up with twist) [24,25,31,37,47,48].
Side Crunch	Participant is in a side-lying position with knees lightly flexed. Upper body is lifted with hands behind the neck and then returned to the starting position. This exercise may vary depending on specific protocols (e.g., arms placed across the chest, side crunch on unstable surfaces) [60,68].
Sit-Up	Participant is in a supine position with feet on the floor (hip-width apart) and knee flexion. Upper body is lifted with hands behind the neck and then returned to the starting position. The exercise is similar to the curl-up or crunch, but the main difference is that the aim of the sit-up is to lift the trunk until the participant is upright in a semi-seated position. This exercise may vary depending on specific protocols (e.g., sit-ups on unstable surfaces) [16,25,58,60].
Roll-Up	Participant is in a supine position with the posterior chain lying down on the floor. The participant is asked to breathe in and tuck the chin in toward the body. Then, the participant is asked to breathe out while rolling up and lifting the upper body [72].
V-Sits	Participant is in a supine position on the floor with the arms the head in addition to hip and knee extension. The participant is instructed to lift the legs through a hip flexion movement (45°) and lift the arms towards the ankles [25].
Bilateral Leg Raise	Participant is in a supine position with palms down on the floor. The participant raises both legs with a hip flexion movement while keeping the knees extended [42,48].
Straight One-Leg Hold	Participant is in a supine position with hands on the abdomen. One foot is lifted with hip flexion movement (straight one-leg hold, 45°). The supporting leg keeps knee flexion and one foot on the floor. This exercise may vary depending on specific protocols (e.g., foam roll or balance cushion as foot support) [39,67,72].
Double Leg Stretch	Participant is in a supine position, with the hip and knees flexed toward the core and the hands touching the patella. The exercise is performed with simultaneous upper and lower limb extension while the head, shoulders, arms, and legs remain off the supporting base [41].
Leaning Forward	Participant is in a kneeling position while hanging from a sling system with the proximal forearm leaning forward, as well as drawing in the lower abdomen after expiration (until 90° shoulder flexion) [43].
Back Extension	Participant is in a prone position, keeping the neutral position of the spine. The participant moves up and down. If the back extension is performed on a bench, the thighs are placed on a pad and the feet are fixed to the bench. This exercise is characterized by the force of gravity. This exercise may vary depending on specific protocols (e.g., one-legged back extension) [25,51,56,68,87].
Prone Leg Extension	Participant is in a prone position with the upper body strapped to the table at the scapula. The leg extension movement is performed by the bilateral flexion and extension of the hip [56].
Bird Dog	Participant is in a prone position with knees under the hips and hands under the shoulders. The participant raises the right arm with a 180° shoulder flexion and the left leg with hip extension. In consequence, if the left arm is raised, the right leg performs the hip extension. This exercise may vary depending on specific protocols (e.g., static or dynamic bird dog, bird dog with hip abduction, bird dog with loads) [45,71,85].
Bridge	Participant laid in a supine position with knees flexed (90°) and feet on the floor. The hip is lifted in a hip extension movement, keeping a straight line between the shoulders and the knees. This exercise may vary depending on specific protocols (e.g., suspended bridge, bridge with hamstring curl on Swiss ball, unilateral bridge or supine plank on suspension systems) [25,45,48,50,52,61,64,66,72,81,82].
Front Plank	Participant in prone position with posterior pelvic tilt and body weight supported by the forearms and feet. The feet are shoulder-width apart and the spine keeps its neutral position. This exercise may vary depending on specific protocols (e.g., front planks with hands and/or legs on suspension systems or unstable surfaces) [25,26,28,29,32,42,45,50,54,57,60,62,66,78,81].
Lateral Plank	Participant in side-lying position with the elbow beneath the shoulder, making a 90° angle (forearm is placed on the floor). The hip is lifted with spine in its neutral position and knees extended in order to keep a straight line from the head to the feet. This exercise may vary depending on specific protocols (e.g., suspended lateral plank, lateral plank on knees, remove the forearm from the floor and keep elbows extended) [25,27,29,45,60,81].
Stable Roll-Out Plank	Participant is in a prone position with feet, knees, and hands on the floor. The participant rolls out with the elbows extended until the hip and knees are aligned. This exercise may vary depending on specific protocols (e.g., suspended roll-out plank) [19,29].
Abdominal Drawing-In Maneuver	Participant is in a supine position with the knees flexed and feet on the floor. This exercises increases the abdominal pressure by pulling the abdominal walls to the inside [72].
Climax Laughter	Participant in standing position with feet on the floor. The participant starts to laugh after a deep intake of breath [31].
Bracing	Participant is in a supine position with knees flexed. The participant is instructed to contract the abdominal muscles followed by two breaths while keeping the contraction [25].
Hollowing	Participant is in a supine position with knees flexed. The participant is instructed to draw in the abdominal muscle towards the spine [25,73].
Lewit	Participant is in a supine position with the hip and knees flexed (90°). The participant is instructed to follow a regular breath pattern. Then, the participant is instructed to purse the lips as if breathing through a straw. Full effort is required to expel the air [73].
Maximum Expiration	The participant, who is in a supine position, is instructed to hold the breath after maximum expiration with an open airway [27].
Stir-The-Pot	Participant is in a prone position with feet on the floor and elbows under the shoulder and the forearm on a Swiss ball. The participant continually moves forearms in a clockwise manner while keeping the spine in its neutral position [32].
Suspended Pike	Participant is in a prone position similar to a front plank on a suspension system (with hands on the floor and feet suspended). The hip is flexed (90°) while keeping the knees fully extended [19].
Suspended Body Saw	Participant is in a prone position similar to a front plank on a suspension system (with hands on the floor and feet suspended). The shoulders are flexed and the elbows are extended in order to push the body forward and backward [19].
Suspended Knee-Tuck	Participant is in a prone position similar to a front plank on a suspension system (with hands on the floor and feet suspended). The elbows are extended, the hips and knees are flexed (90°) in order to move the knees forward and backward [19].
5-min Shaper Device	Participant in prone position with hands on a handlebar. The knees are placed on a supporting surface of the device in order to perform hip flexion and extension. The angle of the device relative to the ground may be modified based on four levels of intensity (beginner, intermediate, advanced, and extreme) [37].
Supine Lumbar Setting on Sling	Participant is in a supine position with arms on the abdomen, hip flexion (90°), and knee flexion (90°). The legs hang from a sling [36].
Side-Lying Lumbar Setting on Sling	Participant is in a side-lying position with the head, chest, and legs hanging from slings [36].
Prone Lumbar Setting on Sling	Participant is in a prone position with the head, chest, and legs hanging from slings [36].
Copenhagen Adduction	Participant is in a side-lying position with one forearm (e.g., right forearm) as support on the floor. The leg on the forearm side (i.e., right leg) is also on the floor, providing stability to the body through the ankle. The other leg is held by another partner at its hip’s height. The participant is instructed to perform a hip adduction and then return to the starting position [75].
Hip Adduction with an Elastic Band	Participant is in a standing position with an elastic band on the leg, which is placed closer to the band’s fixation point. The aim is to adduct the hip while maintaining balance with the other foot [75].
Hip Adduction on an Adductor Machine	Participant is in a sitting position on a hip adduction machine. The participant has to adduct the hip since the machine adds resistance towards maximal hip abduction [75].
Hip Adduction against a Partner’s Hip Abduction	This exercise requires two participants who are sitting on the floor. Both of them have their hands placed on the floor behind the trunk. The tested participant places the legs with the knees extended and the feet and lower shin on the outside (i.e., distally) of the partner’s feet and lower shin while performing an adduction, which is balanced by the partner’s abduction [55].
Hip Abduction against a Partner’s Hip Adduction	This exercise requires two participants who are sitting on the floor. Both of them have their hands placed on the floor behind the trunk. The tested participant places the legs with the knees extended and the feet and lower shin medially on the partner’s feet and lower shin while performing an abduction, which is balanced by the partner’s adduction [55].
Sliding Hip Abduction/Adduction Exercise	Participant is in a standing position with hands on the hip. One foot is placed on a washcloth in order to slide it laterally by abducting the hip; it is then returned to the starting position [75].
Side-Lying Hip Adduction	Participant is in a side-lying position, with the side-lying leg (e.g., right leg) straight and the left leg with hip and knee flexion (90°). The aim is to lift the right leg by hip adduction [75].
Supine Hip Adduction	Participant is in a supine position with the hip and the knees in 90° flexion. The aim is to perform maximal hip abductions and return to the starting position by hip adduction [75].
Isometric Ankle Adduction against a Ball	Participant is in a supine position with knees extended. The participant has to press against a ball, which is placed between the ankle [55,75].
Isometric Knee Adduction against a Ball	Participant is in a supine position with knees flexed. The participant has to press against a ball, which is placed between the knees [55,75].
Standing One-Leg Cross-Country Skiing	Participant is in a unilateral standing position. It is a coordination exercise in which the knee is continually flexed and extended while swinging the arms [55].
Folding Knife	Participant is in a supine position with a ball between the knees. The repetitions are performed by the participant combining a sit-up with hip and knee flexion [55].
Forward Lunge	Participant is in a standing position with feet shoulder-width apart. One step forward is taken in the sagittal plane. The participant lowers the body (spine in neutral position) with 90° hip and knee flexion [48].
Push-Up	Participant is in a prone position with shoulders abducted and elbows extended. The toes are placed shoulder-width apart. When flexing the elbows, the participant lowers the body and pushes back up by extending the elbows. This exercise may vary depending on specific protocols (e.g., push-ups on suspension systems with hands and/or legs on the suspension system, push-ups with hands and/or legs at different heights) [17,35,50,70,79,80].
Back Squat	Participant is in a standing position with fully extended knees and a natural sway in the lower back. The barbell is placed behind the neck. The participant lowers the load (using a self-paced but controlled tempo) such that the fulcrum of the hip is equal to the fulcrum of the knees (full squat). All parts of the feet are in contact with the floor. This exercise may vary depending on specific protocols (e.g., back squat on unstable surfaces, on Smith machine, different loads, or half-squat) [28,30,38,44,48,53,69,74,77,83].
Bulgarian Squat	Participant is in a standing position with feet on the floor. One step forward is taken with the front leg and the other one in the back is placed on a bench. The distance between the bench and the front leg is ~80% of the leg length. Then, the barbell is placed behind the neck. The aim of the exercise is to lower the load by squatting with the front leg [30].
Front Squat	Participant is in a standing position with fully extended knees and a natural sway in the lower back. The barbell is placed behind the neck. The movement is similar to the back squat but the main difference is that the barbell is placed across the front side of the shoulders [69].
Deadlift	The participant, in a standing position with feet shoulder-width apart, has to lower the body in order to lift the barbell until the hip is fully extended while maintaining a neutral spine position. This exercise may vary depending on specific protocols (e.g., Romanian deadlift, stiff leg, hexagonal bar deadlift) [40,44,46].
Hip Thrust	Participant is in a seated position on the floor with the upper back on a bench and knees flexed at 90°. The barbell is placed above the pelvis and the spine is maintained in a neutral position. The aim is to lift the barbell with a hip extension movement (i.e., hip thrust) [46].
Kettlebell Swing	Participant is in a squatting position with one hand (e.g., right hand) holding a kettlebell. The participant moves the kettlebell in the sagittal plane by rapidly extending the knees and hip until reaching the chest level. This exercise may vary depending on specific protocols (e.g., standing position as starting position, bilateral swings) [33,49,63].
Kettlebell Snatch	Participant in squatting position with one hand (e.g., right hand) holding a kettlebell (similar to the swing technique). The participant swings the kettlebell into a snatch position and the kettlebell is caught overhead. The force is absorbed by flexing the knees and hip as the participant performs the catch. In addition, the participant is told to keep the elbow extended (not locked) and hold the kettlebell overhead for a few seconds (e.g., two seconds) before going back to the starting position. This exercise may vary depending on specific protocols (e.g., standing position as starting and ending position, swings overhead) [33,49].
Kettlebell Clean	Participant in squatting position with the feet slightly wider than the shoulders. The participant reaches down to grasp the kettlebell with one hand (e.g., right hand) and pulls it up close to the body so that the elbow is high with shoulder abduction and elbow flexion. Once the bell is pulled high, the elbow and hand drop while the shoulder is performing external rotation. The kettlebell flips over the hand and it is caught posterior to the vertical forearm. Then, the participant absorbs the force by knee and hip flexion [49].
Clean and Jerk	The participant is in a standing position with feet shoulder-width apart has to lower the body in a squatting position in order to grasp the barbell with both hands. The participant pulls the barbell up (as much as possible) close to the body in addition to tripling lower limb extension (ankle, knee, and hip). Then, the barbell is received in front of the neck (resting on the shoulders) while getting into a squat position. Finally, the bar is lifted upwards while keeping the torso erect, feet flat on the floor, and the bar slightly behind the head [65].
Bent-Over Row	Participant is in a standing position with feet shoulder-width apart. Although the knees are flexed in order to lean the trunk forward from the waist, the spine remains neutral. The hands hold the bar slightly wider than shoulder-width apart with elbows extended. The aim of the exercise is to row the weight up until it touches the upper part of the abdomen [44].
Inverted Row	Participant is in a supine position with heels on the floor. The participant holds a barbell wider than shoulder width and pulls up in order to continually bring the chest to the barbell. This exercise may vary depending on specific protocols (e.g., suspended inverted row, inverted row with pronated grip) [50,59,66,68].
Kneeling Rotational Throw	Participant is in a short lunge position (one knee on the ground). Knees (hip-width apart) and shoulders remain in the same direction (perpendicular to the target: wall or partner). The aim is to perform a rotational throw with a heavy ball [44].
Bench Press	Participant is in a supine position with feet on the floor and spine in its neutral position on a higher surface (i.e., bench). The hands grasp the barbell wider than shoulder width and the participant lowers it to the chest. Once the barbell touches the chest, the barbell is pushed upwards until the elbows are extended. This exercise may vary depending on specific protocols (e.g., bench press on unstable surfaces, unilateral bench press) [34,76,79,84].
Standing Cable Press	Participant is in a standing position in the center of the pulleys with the feet shoulder-width apart. Once the spine is in its neutral position, the scapula is retracted, the elbows are flexed (90°), the shoulders abducted (45°), and the handles are moved forward by extending the elbow [79].
Chest Press on Suspension Device	Participant is in a prone position with heels on the floor, hips and knees extended. The participant holds onto the straps of the suspension system in order to perform a similar movement to push-ups by continually flexing and extending the elbows while maintaining the neutral position of the spine [66].
Dumbbell Press	Participant is in a sitting position with the feet shoulder-width apart and the knees flexed (90°, seated dumbbell press) or extended (standing dumbbell press). The participant holds the dumbbells with the thumb-side towards the ears. The aim of the exercise is to press the dumbbells straight forward while the spine maintains its neutral position. When doing the seated dumbbell press, the bench supports the back of the participant. This exercise may vary depending on specific protocols (e.g., unilateral seated dumbbell press, unilateral standing dumbbell press) [86].
Triceps Dips	Participant is in a sitting position with hands on push-up handles and feet elevated. The aim of the exercise is to lower the body by flexing the elbows and then lifting the body again [68].

°: degrees.