The interference effect associated with concurrent training (CT) has been widely debated. A recent model suggests that including sprint interval training (SIT) as the endurance component may attenuate this effect. However, studies examining the impact of SIT-based CT on neuromuscular and cardiorespiratory adaptations are limited. This systematic review and meta-analysis evaluated the effects of CT programs including SIT on strength, hypertrophy, maximum oxygen consumption (VO₂max), and sprint performance. Searches were conducted in PubMed, Embase, and SPORTDiscus, following PRISMA 2020 guidelines. Randomized controlled trials in healthy adults (≥18 years) comparing SIT-based CT with resistance training (RT) alone, including at least six supervised sessions over two weeks, were eligible. Nine studies (187 participants) met inclusion criteria. Pooled analyses showed no significant differences between SIT+RT and RT alone for lower-body strength (SMD: 0.01; p=0.94), upper-body strength (SMD: −0.06; p=0.83), jump performance (SMD: 0.11; p=0.11), or sprint performance (SMD: −0.01; p=0.95). However, SIT+RT significantly improved VO₂max compared with RT alone (SMD: 0.78; p=0.001). Sensitivity analysis revealed greater jump gains with short sprint protocols (≤10 s) (SMD: 0.41; p=0.025). These findings indicate that SIT within CT enhances cardiorespiratory fitness without compromising strength or power and may potentiate jump performance when short sprints are used.
Farro et al. (Tue,) studied this question.