Introduction and purposeThe effectiveness of endurance training at low to moderate intensities targeted at the level of maximal lipid oxidation (LIPOXmax) is confirmed by recent international work. It may seem paradoxical, given the low level of caloric expenditure involved. One of the explanations for this paradox is that LIPOXmax training has epigenetic effects and regulatory effects on eating behavior. Indeed, exercise at this level favors satiety and reduces the urge to snack, whereas at higher intensity, in the lipid oxidation zone, 30 to 60 minutes of endurance exercise favors food intake and may determine a paradoxical weight gain.Methods and resultsIn our previously published database of 3739 calorimetries we have recalculated the kinetics of the lipid/carbohydrate oxidation ratio and we observe that it peaks on average 12% below LIPOXmax (39.45% ± 0.20% vs. 44.87% ± 0.23% VO2max; P < 0.0001) at a level we propose to call “optimal level of fat/carbohydrate oxidation ratio” (OLORFOX) and that this level may present in many cases wide inter-individual variations, so that there are profiles of subjects in whom it is frankly disjointed from that of LIPOXmax. A preliminary series of 11 patients with this profile who were trained at OLORFOX confirms that this approach over 3 years is effective for weight loss (−11.5 ± 1.5% of initial weight P < 0.001), even though this level is set below the LIPOXmax which is itself located at a low to moderate intensity.ConclusionThese preliminary data lead us to study more widely this type of targeting of training in overweight individuals.