Effects of the intensity of interval training on aerobic fitness, body composition and resting metabolic rate of women with overweight or obesity: A randomized trial

Article type: Research Article

Authors: Andreato, Leonardo Vidal^{a; b; *} | Andrade, Alexandro^a | Keech, Andrew^c | da Silva, Valmir^d | Francisco, Walker William^d | Milani, Felipe Tiburcio^d | de Souza Genta, Laura^e | Branco, Braulio Henrique Magnani^{d; e; f}

Affiliations: [a] Sport and Exercise Psychology Laboratory (LAPE), Santa Catarina State University, Florianópolis, SC, Brazil | [b] School of Health Sciences, University of Amazonas State, Manaus, AM, Brazil | [c] School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia | [d] Physical Education Department, University Center of Maringá, Maringá, PR, Brazil | [e] Medicine Department, University Center of Maringá, Maringá, PR, Brazil | [f] Graduate Program of Health Promotion, University Center of Maringá, Maringá, PR, Brazil

Correspondence: [*] Corresponding author: Leonardo Vidal Andreato, Sport and Exercise Psychology Laboratory, Physical Education Department, University of Santa Catarina State, Rua Pascoal Simone, 358 – Coqueiros, 88080-350, Florianópolis, Brazil. E-mail: vidal.leo@hotmail.com.

Abstract: BACKGROUND: Moderate-intensity interval training (MIIT) may be a viable exercise format for improving body composition, aerobic fitness, and health-related variables. OBJECTIVES: This randomized trial aimed to analyze the effect of MIIT or high-intensity interval training (HIIT) on aerobic fitness, body composition variables, and resting metabolic rate (RMR) in women with overweight or obesity. METHODS: 31 sedentary adult women with overweight or obesity performed 7 weeks × 3 weekly sessions of either HIIT or MIIT. Physical and physiological tests were applied before and after training. RESULTS: In both analyses (intention-to-treat and by adherence to the training), aerobic fitness showed a time effect (p= 0.041 and p= 0.015), but without differences between groups (p> 0.05). No group (HIIT vs. MIIT), time (pre vs. post), or interaction effects (group vs. time) were found for RMR, body composition markers (fat mass, body fat percentage, lean mass), or body mass index – BMI (p> 0.05). In addition, MIIT induced a relatively high drop-out rate. CONCLUSIONS: This study suggested that the short-term (7-weeks) interval exercise training was effective for increasing aerobic fitness, and moderate-intensity intervals were as effective as high-intensity intervals. However, neither training format was effective for changing RMR, body composition variables, or BMI of women with overweight or obesity. Clinical trial ID: RBR-9jd7b7.

Keywords: High-intensity interval training, moderate-intensity interval training, overnutrition, physical fitness, sedentary behavior

DOI: 10.3233/IES-220067

Journal: Isokinetics and Exercise Science, vol. 31, no. 2, pp. 127-136, 2023