Acute Effects of Concurrent High-Intensity Interval Cycling and Bench-Press Loading on Upper- and Lower-Body Explosive Strength Performance.

Abstract

This study examined the acute effects of lower-body high-intensity interval loading (HIIT) on explosive upper- and lower-body strength, as well as the combined effect of HIIT and bench-press loading versus HIIT and squat loading on the explosive upper- and lower-body strength. Fifteen physically active men completed 2 sessions consisting of HIIT (4 × 4min cycling at 80% of peak power output) immediately followed by lower- (HIIT + LBS) or upper-body (HIIT + UBS) strength loading (3 × 5 + 3 × 3 repetitions at 80% 1-repetition maximum [ie,6 sets in total]) in a randomized order. Squat and bench-press mean propulsive velocity (MPV) was assessed before HIIT (T0), immediately after HIIT (T1), immediately after the strength loading (T2), and 24hours after the experimental session (T3). Squat MPV decreased to a similar magnitude at T1 in HIIT + LBS (-5.3% [7.6%], P = .117, g = .597) and HIIT + UBS (-5.7% [6.9%], P = .016, g = .484), while bench press remained unchanged (-1.4% [4.7%], P = 1.000, g = .152, and -1.0% [7.0%], P = 1.000, g = .113, respectively). Both squat and bench-press MPV were statistically reduced at T2 compared to T0 (HIIT + LBS: -7.5% [7.8%], P = .016, g = .847, and -6.8% [4.6%], P < .001, g = .724; HIIT + UBS: -3.9% [3.8%], P = .007, g = .359, and -15.5% [6.7%], P < .001, d = 1.879). Bench-press MPV at T2 was significantly lower in HIIT + UBS when compared to HIIT + LBS (P = .002, d = 1.219). These findings indicate lower- but not upper-body explosive strength to be acutely reduced by preceding lower-body HIIT. However, lower-body HIIT combined with either upper- or lower-body strength loading resulted in a similar acute reduction of both squat and bench-press explosive strength.