Comparison of hormone responses following light resistance exercise with partial vascular occlusion and moderately difficult resistance exercise without occlusion

Abstract

Previous studies of contracting muscle with low loading and partial vascular occlusion demonstrated hypertrophy and strength adaptations similar to and exceeding those observed with traditional moderate to high resistance (Shinohara M, Kouzaki M, Yoshihisa T, and Fukunaga T. Eur J Physiol 77: 189-191, 1998; Takarada Y, Takazawa H, Sato Y, Takebayashi S, Tanaka Y, and Ishii N. J Appl Physiol 88: 2097-2106, 2000; Takarada Y, Sato Y, and Ishii N. Eur J Physiol 86: 308-314, 2002). The purpose of the study was to determine the anabolic and catabolic hormone responses to light resistance exercise combined with partial vascular occlusion. Three experimental conditions of light resistance with partial occlusion (LRO), moderate resistance with no occlusion (MR), and partial occlusion without exercise (OO) were performed by eight healthy subjects [mean 21 yr (SD 1.8)]. Three sets of single-arm biceps curls and single-leg calf presses were completed to failure with 1-min interset rest periods. Workloads of 30 and 70% one repetition maximum for each exercise were lifted for the LRO and MR trials, respectively. Blood samples were taken preexercise, postexercise, and 15 min postexercise for each experimental condition. Lactate increased significantly in the LRO and MR trials and was not significantly different from each other at any time point. Growth hormone (GH) increased significantly by fourfold from pre- to postexercise in the LRO session but did not change significantly during this time period in the MR and OO trials (8.3 +/- 2.3 vs. 2.1 +/- 1.2 and 2.6 +/- 0.94 microg/l; respectively, P < 0.05). There were no changes in resting total testosterone [T; mean 15.7 +/- 1.6 (SE) nmol/l], free testosterone (FT; 54.1 +/- 4.5 pmol/l), or cortisol (267.6 +/- 22 nmol/l) across all trials and times. In conclusion, with similar lactate responses, light exercise combined with partial vascular occlusion elicits a greater GH response than moderate exercise without occlusion but does not affect T, FT, or cortisol.

Exercise and Blood Flow Restriction

“…However, during the BFR condition, the time course of the lactate response indicated that metabolites were retained and had accumulated in the working muscle. This finding was similar to Reeves et al (76), who compared low--intensity (30% of 1RM) elbow flexion and plantar flexion with BFR (cuff pressure set at 20 mm Hg below resting systolic pressure for upper body and 40 mm Hg above upper body occlusive pressure; cuff width not reported) to moderate intensity without BFR (70% of 1RM) and found equivalent lactate responses, albeit a larger GH response in the low intensity with BFR condition. This would seem to indicate that lactate (and the associated metabolic acidosis) is not the only modulator of the GH response to BFR exercise.…”

“…Numerous studies have found that the ischemic (88) and hypoxic (92) intramuscular environment associated with BFR protocols induces a greater rate of ATP hydrolysis, exaggerated PCr depletion (85) decreased pH (84,85), and an increased lactate response (26,74,76,88,89). Suga et al (84) found greater metabolic stress (i.e., PCr, Pi, and deprotonated phosphate) via 31P--magnetic resonance spectroscopy, during low--intensity exercise (20% of 1RM) with BFR (varying pressure; 18.5--cm cuff width) vs. lowintensity (20% of 1RM) without BFR.…”

“…Furthermore, Goto et al (32) reported that a "hypertrophy" type regimen that elicited greater acute GH release was associated with greater longitudinal increases in quadriceps CSA vs. a "strength" type regimen. Studies that have compared resistance exercise protocols with or without BFR have demonstrated a significantly greater systemic GH release subsequent to the BFR protocol (26,74,76,89). Hence, a key mechanism underlying the BFR induced hypertrophy might be the increased duration of metabolic acidosis that evokes systemic GH release.…”

“…A recent review by Loenneke et al (56) indicated minimal acute and chronic testosterone changes subsequent to BFR plus exercise. Studies that examined the total testosterone (3,26,76) and free testosterone responses (3,76) to BFR have indicated no significant increases. However, the lack of testosterone response may have been attributable to the low exertion type of exercise mode (Abe et al (26) examined low--intensity (4 sets; 30 repetitions first set, followed by 3 sets of 15 repetitions at 20% of 1RM; 30--second rest intervals between sets) bilateral knee extension with and without BFR (200 mm Hg; cuff width not reported) on acute markers of muscle damage (e.g., IL--6, CK, and myoglobin) before, immediately after, 24 hours after, and 48 hours postexercise.…”

I SAFS UniCatólica 2015

“…No nosso estudo, ficou evidente que o treino sob oclusão vascular induziu aumentos significativos do lactato sanguíneo em diferentes momentos (meio e final do treino) quando comparados aos valores basais, bem como no grupo que treinou sob alta intensidade, que apesar de não ter sido observada a significância, observou-se valores altos de lactato. Em um estudo conduzido por (Reeves et al, 2006), as concentrações de lactato foram similares no grupo submetido ao treino com oclusão vascular e também no grupo que treinou com resistência moderada sem oclusão. Porém, as concentrações de GH foram maiores no grupo que treinou sob oclusão.…”