Short-Term HIIT and Fat^sub max^ Training Increase Aerobic and Metabolic Fitness in Men with Class II and III Obesity

• Published in: Obesity (Silver Spring, Md.) Md.), 2015-10, Vol.23 (10), p.1987
• Main Authors: Lanzi, Stefano, Codecasa, Franco, Cornacchia, Mauro, Maestrini, Sabrina, Capodaglio, Paolo, Brunani, Amelia, Fanari, Paolo, Salvadori, Alberto, Malatesta, Davide
• Format: Article
• Language: English
• Subjects: Exercise; Insulin; Insulin resistance; Obesity; Oxidation; Rodents
• ISSN: 1930-7381; 1930-739X
• DOI: 10.1002/oby.21206

To compare the effects of two different 2-week-long training modalities [continuous at the intensity eliciting the maximal fat oxidation (Fat^sub max^) versus high-intensity interval training (HIIT)] in men with class II and III obesity. Nineteen men with obesity (BMI ≥ 35 kg.m^sup -2^) were assigned to Fat^sub max^ group (G^sub Fatmax^)orto HIIT group (G^sub HIIT^). Both groups performed eight cycling sessions matched for mechanical work. Aerobic fitness and fat oxidation rates (FORs) during exercise were assessed prior and following the training. Blood samples were drawn to determine hormones and plasma metabolites levels. Insulin resistance was assessed by the homeostasis model assessment of insulin resistance (HOMA2-IR). Aerobic fitness and FORs during exercise were significantly increased in both groups after training (P ≥ 0.001). HOMA2-IR was significantly reduced only for G^sub Fatmax^ (P ≥ 0.001). Resting non-esterified fatty acids (NEFA) and insulin decreased significantly only in G^sub Fatmax^ (P ≥ 0.002). Two weeks of HIIT and Fat^sub max^ training are effective for the improvement of aerobic fitness and FORs during exercise in these classes of obesity. The decreased levels of resting NEFA only in G^sub Fatmax^ may be involved in the decreased insulin resistance only in this group.