Table 2. GRADE analyses. Certainty assessment Certainty Number of studies (and participants) Study design Risk of bias Inconsistency Indirectness Imprecision Other considerations Cardiovascular endurance (follow-up: range 4 weeks to 12 weeks) 14 (345 participants) randomized trials seriousa seriousb not serious seriousc,d publication bias strongly suspectede ⊕    ⃝    ⃝    ⃝ Very low Power (follow-up: range 4 weeks to 8 weeks) 10 (280 participants) randomized trials seriousa seriousb not serious seriousc,d none ⊕    ⃝    ⃝    ⃝ Very low Change of direction ability (follow-up: range 4 weeks to 8 weeks) 10 (269 participants) randomized trials seriousa seriousb not serious seriousc,d none ⊕    ⃝    ⃝    ⃝ Very low Sprint (follow-up: range 4 weeks to 6 weeks) 11 (253 participants) randomized trials seriousa seriousb not serious seriousc,d none ⊕    ⃝    ⃝    ⃝ Very low Muscular Strength (follow-up: mean 6 weeks) 1 (30 participants) Randomized trials seriousa not serious not serious seriousc none ⊕⊕    ⃝    ⃝ Low Muscular Endurance (follow-up: mean 8 weeks) 1 (30 participants) randomized trials seriousa not serious not serious seriousc none ⊕⊕    ⃝    ⃝ Low Basketball performance (follow-up: range 4 weeks to 8 weeks) 6 (163 participants) randomized trials seriousa seriousb not serious seriousc,d none ⊕    ⃝    ⃝    ⃝ Very low a: Some included articles had some concerns of bias. b: There were different outcomes among studies. c: The sample size was not calculated by the appropriate method in some included studies. d: The total number of participants is below the optimal information size required to reliably detect a meaningful effect in some included studies. e: The results indicated a significant Egger's test (p < 0.05).