Acute Hormonal Responses to Intentionally Slow or Maximal Velocity Resistance Exercise in Men

Abstract: Intentionally slow velocity (SLOW) resistance exercise, sometimes called slow tempo, uses purposely slow movement velocity which limits the loads that can be lifted (e.g., <50% 1 repetition maximum [RM]). The purpose of this study was to determine the acute hormonal responses between SLOW and maximal velocity (MAX) resistance exercise when using commonly prescribed training protocols. Ten healthy resistance-trained men performed two randomly ordered exercise sessions consisting of a SLOW session (1 × 10 at 28% 1RM; 10 s concentric and eccentric phases) and a MAX session (3 × 10 at 70% 1RM; maximum concentric velocity) separated seven days apart. Both SLOW and MAX sessions included the barbell parallel squat and bench press exercises. Blood samples were collected pre- and post-exercise, and were analyzed for total testosterone (T), cortisol (C), growth hormone (GH), and lactate (HLa) concentrations. SLOW and MAX both significantly increased C and GH but with no differences between protocols for post-exercise responses (GH [µg L–1], SLOW = 5.6 ± 3.7, MAX = 5.0 ± 3.1; C [nmol L–1], SLOW = 258.5 ± 122.9, MAX = 284.7 ± 142.0). Only MAX significantly increased T above resting values (T [nmol L–1]; PRE = 27.2 ± 6.9, POST = 32.4 ± 8.5). A significant increase in HLa was observed after both protocols, but MAX produced a larger post-exercise response (HLa [mmol L–1], SLOW = 7.8 ± 3.0, MAX = 13.8 ± 2.1). Contrary to suggestions in the lay literature, SLOW resistance exercise did not produce greater hormonal responses than the MAX resistance exercise regimen. © 2022, Pleiades Publishing, Inc.