Acute Effects of Intermittent Foot Cooling on 1 RM Leg Press Strength in Resistance-Trained Men: A Pilot Study

Abstract

Inter-set peripheral cooling can improve high-intensity resistance exercise performance. However, whether foot cooling (FC) would increase 1 repetition maximum (RM) lower-limb strength is unclear. This study investigated the effect of intermittent FC on 1 RM leg press strength. Ten recreational male lifters performed three attempts of 1 RM leg press with FC or non-cooling (NC) in a repeated-measures crossover design separated by 5 days. FC was applied by foot immersion in 10 °C water for 2.5 min before each attempt. During the 1 RM test, various physiological measures were recorded. The results showed that FC elicited higher 1 RM leg press strength (Δ [95% CI]; Cohen's d effect size [ES]; 13.6 [7.6–19.5] kg; ES = 1.631) and electromyography values in vastus lateralis (57.7 [ 8.1–107.4] μV; ES = 0.831) and gastrocnemius (15.1 [-3.1–33.2] μV; ES = 0.593) than in NC. Higher arousal levels (felt arousal scale) were found in FC (0.6 [0.1–1.2]; ES = 0.457) than in NC. In conclusion, the preliminary findings, although limited, suggest intermittent FC has a potential ergogenic role for recreational athletes to enhance maximal lower-limb strength and may partly benefit strength-based competition events.

Foot Cooling between Interval Bouts Enhances Repeated Lower Limb Power Performance: The Role of Delaying Fatigue

“…Obviously, unlike previous cooling strategies on muscles used before (Cheung and Robinson, 2004) or between (Kim and Hurr, 2020) repeated sprint-cycling workouts that did not demonstrate ergogenic effects, the intermittent application of peripheral cooling on the foot took advantage of the cooling benefits on repeated power performance. However, although a previous study demonstrated that FC increased maximal lower limb muscular force (Wu et al, 2021), contrary to expectations, peak power during cycling (i.e., ability to exert force quickly) was not affected by FC. Our findings confirm previous evidence that only mean power and not peak power is affected by various intervention strategies during repeated sprint performance and dynamic resistance exercise workouts (Frikha et al, 2020;Wilk et al, 2020).…”

“…The cooling method with cold-water immersion has been applied in many studies (Cai et al, 2021;Caminita et al, 2020;Wu et al, 2021).…”

“…Peripheral cooling may induce cooling afferent stimuli to the neuromuscular region (Hopkins et al, 2002;Palmieri-Smith et al, 2007) while preventing a decline in muscle temperature that affects muscle contraction velocity (Cross et al, 1996;Ruiz et al, 1993). Collectively, this strategy has boosted strength performance in remote muscle groups from the cooling area, e.g., FC increased leg-press performance (Cai et al, 2021;Wu et al, 2021), and palm cooling increased subsequent sets of bench press performance (Kwon et al, 2010(Kwon et al, , 2015.…”

“…Recent studies report that foot cooling (FC) improves lower limb strength performance in moderate indoor ambient temperature ( Cai et al, 2021 ; Wu et al, 2021 ). In resistance-trained athletes, during four sets of 85%–90% one- repetition maximum (1 RM) leg-press exercise pyramid workouts, interset FC at 10°C for 2.5 min exhibits higher repetitions leading to exhaustion per set, higher total exercise volume without increasing the degree of rating of perceived exertion (RPE), and greater vastus lateralis (VL) muscle activation than non-cooling (NC) conditions ( Cai et al, 2021 ).…”

“…In resistance-trained athletes, during four sets of 85%–90% one- repetition maximum (1 RM) leg-press exercise pyramid workouts, interset FC at 10°C for 2.5 min exhibits higher repetitions leading to exhaustion per set, higher total exercise volume without increasing the degree of rating of perceived exertion (RPE), and greater vastus lateralis (VL) muscle activation than non-cooling (NC) conditions ( Cai et al, 2021 ). In a more recent study, intermittent FC at 10°C for 2.5 min before attempting maximal strength tests resulted in increased 1 RM leg-press strength (7.1%) and higher arousal levels, and recruited more motor units of the agonist muscles during the 1 RM test ( Wu et al, 2021 ). FC, a type of peripheral cooling, refers to the cooling the extremities (palms and feet) that are distal to the exercising muscles ( Cai et al, 2021 ; Caruso et al, 2015 ; Kwon et al, 2010 ) or cooling the joints (ankles and knees) adjacent to the exercising muscles ( Hopkins et al, 2002 ; Palmieri-Smith et al, 2007 ; Pietrosimone and Ingersoll, 2009 ) rather than cooling the muscles themselves.…”