In participants without obesity, serum total IGF‐1 concentrations increased at both 15 and 40 min during exercise (p < 0.001 for both) but did not differ from pre‐exercise levels at 60 min (p > 0.05) (i.e., 15 min post‐exercise). This evidence concerns the gene IGF1 and obesity due to melanocortin 4 receptor deficiency.