The ASSIST trial: Acute effects of manipulating strength exercise volume on insulin sensitivity in obese adults: A protocol for a randomized controlled, crossover, clinical trial

PLoS One. 2024 May 28;19(5):e0302480. doi: 10.1371/journal.pone.0302480. eCollection 2024.

Abstract

Type 2 diabetes mellitus is a disease in which insulin action is impaired, and an acute bout of strength exercise can improve insulin sensitivity. Current guidelines for strength exercise prescription suggest that 8 to 30 sets could be performed, although it is not known how variations in exercise volume impact insulin sensitivity. Additionally, this means an almost 4-fold difference in time commitment, which might directly impact an individual's motivation and perceived capacity to exercise. This study will assess the acute effects of high- and low-volume strength exercise sessions on insulin sensitivity. After being thoroughly familiarized, 14 obese individuals of both sexes (>40 year old) will undergo 3 random experimental sessions, with a minimum 4-day washout period between them: a high-volume session (7 exercises, 3 sets per exercise, 21 total sets); a low-volume session (7 exercises, 1 set per exercise, 7 total sets); and a control session, where no exercise will be performed. Psychological assessments (feeling, enjoyment, and self-efficacy) will be performed after the sessions. All sessions will be held at night, and the next morning, an oral glucose tolerance test will be performed in a local laboratory, from which indexes of insulin sensitivity will be derived. We believe this study will aid in strength exercise prescription for individuals who claim not to have time to exercise or who perceive high-volume strength exercise intimidating to adhere to. This trial was prospectively registered (ReBEC #RBR-3vj5dc5 https://ensaiosclinicos.gov.br/rg/RBR-3vj5dc5).

Publication types

  • Clinical Trial Protocol

MeSH terms

  • Adult
  • Blood Glucose / analysis
  • Blood Glucose / metabolism
  • Cross-Over Studies*
  • Diabetes Mellitus, Type 2 / physiopathology
  • Diabetes Mellitus, Type 2 / therapy
  • Female
  • Glucose Tolerance Test
  • Humans
  • Insulin Resistance*
  • Male
  • Middle Aged
  • Obesity* / physiopathology
  • Obesity* / therapy
  • Randomized Controlled Trials as Topic
  • Resistance Training

Substances

  • Blood Glucose

Grants and funding

This study is supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ: Grant#407975/2018-7 and #402091/2021-3) and by the Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG: Grant#APQ-00008-22). The funders did not and will not have a role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.