(24) SUPRAMAXIMAL WALKOUTS PROTECT AGAINST PERFORMANCE DECREMENTS EXPEREIENCED IN REPEATED SETS OF BACK SQUATS IN RESISTANCE-TRAINED MALES

Background: Post-activation performance enhancement (PAPE) involves the use of voluntary muscle contractions (i.e., conditioning stimulus) to improve subsequent muscular performance. Supramaximal walkouts are a variant of conditioning stimuli commonly used by strength athletes, yet data on the efficacy of this approach are lacking.

Purpose: To determine the influence of performing supramaximal walkouts on subsequent heavy back squat performance in resistance-trained males.

Methods: Fourteen resistance-trained males (age 23.3 ± 2.9 y, body fat 15.1 ± 6.7%, 1RM back squat 2.09 ± 0.37 kg/BW) completed four sessions (³ 72 hours between visits) in a randomized, counterbalanced, crossover study design. The first session included anthropometric measurements while the second visit involved one-repetition maximum (1RM) back squat testing. The final two sessions were the randomized experimental trials. Each experimental trial consisted of a general dynamic warmup and a more specific barbell warmup followed by a single back squat repetition at 92.5% 1RM (PRE). Five min after PRE, participants unracked and walked out with either 110% 1RM (SMW) or 30% 1RM (CON) for a 10 s isometric hold. After a 5 min rest, three back squat repetitions at 92.5% 1RM (POST1, POST2, POST3) were completed with 5 min rest between each repetition. Participants were instructed to complete PRE, POST1, POST2, and POST3 with maximal concentric velocity. Rating of perceived exertion (RPE), average (P_avg) and peak power (P_peak), average (V_avg) and peak velocity (V_peak), and surface electromyography (sEMG) amplitude of the vastus lateralis and gluteus maximus were measured during each repetition. Relative change from PRE was calculated for all variables at POST1, POST2, and POST3 (% Change = (POST – PRE) / PRE). These change scores were used to assess the efficacy of supramaximal walkouts by using a two-way analysis of variance (ANOVA) with walkout x repetition as the two factors.

Results: The average walkout loads were 57.0 ± 10.5 kg for CON and 208.6 ± 39.2 kg for SMW. A significant main effect of condition was found where performing SMWs decreased RPE (p = 0.031) and increased P<sub>avg (p = 0.019) and V_avg (p = 0.040) when compared to CON. There was also a significant main effect of repetition where P<sub>avg decreases over time (p = 0.005).  No interaction effects (p > 0.05) were observed for any of the variables.

Conclusions: Performing supramaximal walkouts at 110% 1RM may help attenuate acute decrements in performance and elevations in perceived exertion that occur with multiple sets of back squats. PRACTICAL APPLICATIONS: Supramaximal walkouts may be a strategy that can be utilized to maintain performance over multiple sets in a strength-based program while minimizing elevations in perceived exertion. Therefore, it is recommended to incorporate them prior to performing heavy back squats in training or competition.

Acknowledgements: None