Table 4.

Characteristics of the included studies.

Study	Competitive level	N	Age (years old)	Sex	Experimental groups (n)	Control groups (n)	Randomization	Study duration (w)	Outcomes extracted	Instruments/tests for measuring the outcomes
Brose et al. [30]	Trained	21	18–19	Men	2 groups (n = ND)	1 group (n = ND)	No	6	Throwing velocity; Throwing accuracy	Throwing at maximal velocity for a target at 35 ft. Accuracy was determined by measuring the distance from the center of the target to the place the ball hit.
Carter et al. [36]	Trained	24	19.7 ± 1.3	ND	1 group (n = 13)	1 group (n = 11)	Yes	8	Throwing velocity	The throwing velocity of each participant was measured using a calibrated JUGS MPH Cordless Radar Gun. The evaluation of maximum throwing velocity was conducted over a distance of 18.44 m (60 feet 6 inches).
DeRenne et al. [31]	Trained	30	16–18	ND	2 groups (n = 20)	1 group (n = 10)	Yes	10	Throwing velocity	The measurement of throwing velocity utilized an electromagnetic radiation radar. The test involved ten baseball pitches, each using a 5-ounce baseball.
DeRenne et al. [34]	Trained	225	16.6 ± 0.6 and 19.6 ± 0.5	Men	2 groups (n = 150)	1 group (n = 75)	Yes	10	Throwing velocity	The measurement of throwing velocity utilized an electromagnetic radiation radar. The test involved fifteen baseball pitches, each using a 5-ounce baseball.
Escamilla et al. [38]	Trained	34	12.5 ± 1.5	ND	1 group (n = 17)	1 group (n = 17)	Yes	4	Throwing velocity	The measurement of throwing velocity was conducted using a calibrated Jugs Tribar Sport radar gun (Jugs Pitching Machine Company, Tualatin, OR, USA). Each participant performed overhand throws from a flat surface with maximum effort, targeting a point positioned at approximately chest level and 13.7 m away.
Escamilla et al. [35]	Trained	58	14–17	ND	3 groups (n = 43)	1 group (n = 15)	Yes	6	Throwing velocity	The throwing velocity was measured using a precision-calibrated Jugs Tribar Sport radar gun, manufactured by Jugs Pitching Machine Company in Tualatin, Oregon, USA. Each participant commenced their throws from a starting line positioned 22.9 m away from a circular target with a diameter of 1.8 m. The center of this target was approximately at chest level, standing at a height of 1.30 m.
Kurland et al. [39]	Trained	20	13–16	Men	1 group (N = 10)	1 group (N = 10)	No	6	Throwing velocity	Not described
Lachowetz et al. [53]	Trained	22	18–22	ND	1 group (N = 12)	1 group (N = 10)	Yes	8	Throwing velocity	The assessment of throwing performance was conducted over a distance of 18.44 m, with velocity being measured using a sports radar gun.
Logan et al. [54]	Trained	39	ND	ND	2 groups (n = 26)	1 group (N = 13)	No	6	Throwing velocity	The players executed a series of 10 throws from a distance of 15 feet, and a velocitimer was employed to measure the throwing velocity.
Lust et al. [16]	Trained	40	20.0 ± 1.5	ND	2 groups (n = 25)	1 group (N = 15)	Yes	6	Throwing accuracy	It was employed the functional throwing-performance index.
McEvoy et al. [37]	National level	18	24 ± 4	Men	1 group (N = 9)	1 group (N = 9)	No	10	Throwing velocity	Throwing velocity was assessed over distances of 18.44 m using the ProSpeed Professional radar gun model from Decatur Electronics to measure the velocity.
Newton et al. [40]	Trained	24	16–23	Men	2 groups (n = 16)	1 group (N = 8)	Yes	8	Throwing velocity	Throwing velocity was assessed over distances of 18.44 m using the ProSpeed Professional radar gun model from Decatur Electronics to measure the velocity.
Potteiger et al. [55]	Trained	21	19.6 ± 1.3	Men	1 group (n = ND)	1 group (n = ND)	Yes	10	Throwing velocity	Throwing velocity was assessed using radar gun technique (RA-GUN G1, Decatur electronics).
Reinold et al. [32]	Trained	38	15.3 ± 1.2	ND	1 group (n = 19)	1 group (n = 19)	Yes	6	Throwing velocity; Injury rate	They delivered 10 fastballs with a standard 5-ounce regulation baseball from a typical pitching mound. The velocity of each pitch was recorded using a radar gun (Stalker Radar). Injury rate was measured after the training program.
Wooden et al. [56]	Trained	27	15.5 ± 1.0	ND	2 groups (n = ND)	1 group (n = ND)	Yes	5	Throwing velocity	Throws executed at a distance of 60 feet were assessed using a calibrated radar gun, specifically the Magnum X Ban radar gun.
Yang et al. [33]	Trained	38	15.3 ± 1.2	ND	1 group (n = 19)	1 group (n = 19)	No	6	Throwing velocity; throwing accuracy	The measurement of throwing velocity entailed employing ten fastballs, each thrown with a standard 5-ounce regulation baseball, from a conventional pitching mound. The radar gun was utilized for the precise determination of the throwing speed.

ND: not described.