Table 3.
Breakdown of studies selected for systematic review
| N | AUTHOR | YEAR | PARTICIPANTS - LEVEL | DESIGN | INTERVENTION | VARIABLES | OUTCOMES |
|---|---|---|---|---|---|---|---|
| 1 | Gual et al. | 2016 | 81 basketball (B) and volleyball athletes, well trained | 24 weeks; 2 groups. Both trained, but IG received additional YoYoTM training. | 4 × 8 YoYoTM squat, 1 × week. | VISA-p, CMJ and squat power: CON and ECC | Squat-CON, Squat- ECC, and CMJ ↑ with YoYoTM VISA-R, VISA-L did not differ between groups |
| 2 | Hérnandez Davo et al. | 2018 | 10 B amateurs | 6 weeks; [flywheel bilateral support (n = 5) vs. flywheel unilateral support (n = 5)]. | 4 x 8 of bilateral or unilateral squat in flywheel device, 2 x week. | Power test in flywheel, CMJ, triple hop test and T-Test (COD) | T-Test and power test in flywheel ↑ in both groups Triple hop test may be greater for unilateral group. |
| 3 | Sánchez-Sánchez et al. | 2019 | 24 B amateurs and soccer players | 5 weeks; [HIT (n = 10) vs. CT (concurrent HIT eccentric overload training) (n = 12)] | Both: 2 HIT sessions; in addition, CT group performed EO (backwards lunges and hamstrings kicks with conical pulley and half-squats (kBox3) 2 × 6 and PI to 3 × 6 during; 2 x week | COD, RSA test, CMJ and 20-m shuttle run test | CT group ↑ COD, RSAbest, RSAmean, RSAslowest and CMJ compared to solely HIT. |
| 4 | Cabanillas et al. | 2020 | 8 B professionals | 8 weeks; EO (n = 4) vs. traditional squat (n = 4)]. | PI in half squat; 4 × 10 to 6 × 10 reps (ProSquat ProInertial), 1 × week. | CMJ and 30-m sprint | EO ↑ CMJ and 30-m sprint |
| 5 | O Brien et al. | 2020 | 20 B amateur females | 4 weeks; [TET (n = 9) vs. FIT (n = 11)] | TET group: 4 x 8 65% (1RM) Back squat (2-s CON and 4-s ECC) FIT group: 4 x 10 (kBox 3); Both 2 x week | Back squat 1RM, CMJ, SJ, 10-m sprint, COD and S&R | 1RM, 10 m and CMJ ↑ for FIT group |
| 6 | Stojanović et al. | 2021 | 36 B players, well trained | 8 weeks; [FST (n = 12) vs. TST (n = 12)] vs. CON (n = 12) | FST (D11 full device) and TST: One-arm dumbbell row, biceps curls, RD and HS (PI from 2 x 8 to 4 x 8) and rotational pall-of press (from 2 × (2 × 12−15) to 2 × (4 × 12−15); 1−2 x week | Lower limb isometric strength (ISOMET), 5 and 20-m sprint time, CMJ and T-test | ISOMET, CMJ and t-test ↑ FST than TST. ISOMET, CMJ, 5-m sprint and t-test ↑ FST than CON group. |
| 7 | O Gonzalo-Skok et al. | 2022 | 24 elite youth B players | 6 weeks; [VUL (n = 12) vs. VUH (n = 12)] | VUL group: Side-step, backward lunges, crossover cut & landing. VUH group: Lateral squat, shuffling step, lateral crossover & 90º lunge. 2 x week; Both PI from 1x6 to 1x10 with Versa Pulley. | CMJ, LJ & HJ, 5 and 20-m sprint time, modified 505 test, V-cut test & LSI | CMJ, HJ, LJ, LSI & 180º COD ↑ both groups. LJ ↑ VUL than VUH group |
Legend: IG, intervention group; VISA-p, Victorian Institute of Sports Assessment patellar tendinopathy questionnaire; CON, concentric; ECC, eccentric; CMJ, countermovement jump; HIT, high-intensity training; EO, eccentric overload; PI, progressive increase; RSA, repeat sprint ability; TET, tempo eccentric training; FIT, flywheel inertial training; SJ, squat jump; COD, change of direction; S&R, sit and reach test; FST, flywheel strength training; TST, traditional strength training; CON, control; RD, Rumanian deadlift; HS, half-squat. VUL, variable unilateral training; VUH, variable unilateral horizontal; LJ; lateral jump; HJ, horizontal jump; LSI, limb symmetry index.