Inter-Effort Recovery Intermittent Hypoxia and Force Parameters in Sprint Interval Exercise

Performing training sessions in hypoxia leads to a decrease in effort quality. The inter-effort recovery intermittent hypoxia model seems to ensure training session performance. The aim of this study is to investigate the effects of sprint interval exercise under normoxic (NOR), continuous hypoxic (HYP), and inter-effort hypoxic (IEH) conditions on force parameters. Seven swimmers (age: 26.04 ± 4.64 years) volunteered and performed one session of the 10 × 30-s all-out tethered swimming efforts with 4-min passive recovery intervals for each condition. Considering the simulated altitude at F_iO₂ = 0.13 and NOR at F_iO₂ = 0.209. The sessions were separated at least 48 hours. The peak force (PF), mean force (MF), impulse, fatigue index (FI) and percentage mean force relative to peak force (PF_PERC) were determined for each effort. The force parameters were higher on IEH (PF: Δ = 21.32 N; MF: Δ = 9.65 N; impulse: Δ = 626.78 N·s) and HYP (PF: Δ = 15.80 N; MF: Δ = 6.92 N; impulse: Δ = 621.77 N·s) in relation of the NOR (p < 0.001). PF_PERC evidenced lower values in IEH in relation to HYP (Δ= 3.1 %, p = 0.017). The HYP and IEH condition can be considered a model that enhances performance in force parameters compared to the NOR condition.