Compelling evidence indicates that resistance training (RT) improves muscular strength, functional capacity, and muscle quality in individuals undergoing bariatric surgery (BS) [1], despite inconsistent changes in fat-free mass, skeletal muscle mass or muscle cross-sectional area [2]. However, recent evidence revealed that the intensity of RT in exercise interventions following BS is often poorly reported [3], which hinders knowing the effect of a certain training load and limits clinicians’ and exercise professionals’ capacity to replicate exercise interventions in clinical settings. Accurate prescription and monitoring of RT intensity is crucial for i) applying both progression and individualization training principles [4], ii) improve our understanding of the specific RT dose driving the benefits associated with RT following BS, iii) enhance the quality of this scientific field by optimizing exercise interventions following BS.

In most exercise-based trials following BS, RT intensity is prescribed based on either a percentage of a one-repetition maximum (1RM) test (%1RM), or the maximal number of repetitions that can be completed to failure with a given submaximal load (nRM) [3]. Progression and individualization are key training principles that determine individual adaptations and have been poorly applied in exercise-based BS clinical trials [4]. While progression involves a gradual increase in the training stimulus (i.e., intensity, volume, frequency, etc.), individualization refers to adjusting the training stimulus based on the participant’s physical fitness [4]. It has been shown that the 1RM can rapidly increase during the initial weeks of a RT intervention in trained and untrained individuals [4, 5], which has important implications if the 1RM testing is performed only once at the beginning of the RT program. For example, let us suppose that the target intensity for an individual following BS with a baseline 1RM of 50 kg in the bench press is set at 60% of 1RM for the first four weeks. The initial absolute load for this individual would be 30 kg. However, if the 1RM increases by 10% after 1-2 weeks of RT, the new 1RM would be 55 kg, making 30 kg now represent 54.5% of 1RM instead of the prescribed 60%. This discrepancy is likely to occur in most BS trials where 1RM assessment is traditionally performed only once before initiating the RT program and is not reassessed as the program progresses. Consequently, even if the RT program produces a health-related benefit, it becomes impossible to determine the dose-response relationship (i.e., what intensity of exercise produces the benefit). Moreover, given that BS-induced weight loss could significantly impact muscular strength in the short term [6], proper monitoring of RT intensity becomes essential to facilitate individual adjustments during the initial stages of the exercise intervention.