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Updated: Jan 24, 2026

Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans
Published on: October 17, 2018
Acute responses of isometric handgrip exercise combined with blood flow restriction in the elderly
Thailson Fernandes da Silva1, Leandro Lima de Sousa2, Johnatan Campos Sousa Leite3
1Graduate Program in Physical Education, Catholic University of Brasília.
Abstract:
This study aimed to investigate the influence of isometric handgrip exercise under different blood flow restriction times on acute responses related to safety and effectiveness in the elderly. Eleven physically active elderly people (70.1 ± 7.1 years) were subjected to three protocols (P1-1m), (P2-30s) and (P3-Control) of isometric handgrip contraction. Hemodynamic markers (SBP, DBP and HR), hematological markers (D-dimer, fibrinogen, APTT and ultrasensitive CRP) and surface electromyography (sEMG) of the flexor digitorum superficialis and extensor digitorum communis muscles were analyzed. The hemodynamic variables showed no significant difference P < 0.05 between the moments before, immediately after, after 15 minutes, and after 30 minutes. The hematological variables showed no significant difference P < 0.05 between the pre- and post-30 minute time points. The sEMG variables showed a significant difference of p< 0.01 at the beginning, middle and end of each series and between the complete series for both muscles analyzed. In line with the aim of this study, we can accept the hypothesis that the P1-1m, P2-30s and P3-Control protocols are safe. However, we reject the hypothesis that the BFR protocols result in greater muscle activation compared to the protocol without BFR.
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