Accuracy of Prediction Equations to Calculate Maximum Strength

Resistance exercise training (RT) is a key component of health related exercise programs. However, an accurate specification of RT load prescription is essential for effective and safe achievement of training aims. Proper specification of exercise intensity might be the most critical issue when designing RT protocols for adults. One repetition maximum tests (1RM) have been considered the "gold standard" of dynamic maximum strength evaluation. Although the argument of increased risk of injuries and adverse effects with 1RM testing in older people has been rejected by several studies , limited motivation to lift maximum loads, requirement for high test effort, time constraints, and interruption of the continuity of the training process aggravate the frequent application of 1RM tests particularly in non-athletic RT. 1RM prediction equations that use the load and number of repetitions completed to fatigue (RTF) to predict repetition maximum might be a reliable and feasible option to 1RM testing. Thus, the primary aims of this study were to evaluate the predictive accuracy of current RTF equations and to develop an equation that more accurately predicts 1RM from RTF tests.

Inclusion Criteria: * 18 to 35 years old * 60 to 85 years old Exclusion Criteria: * Contraindication for one repetition maximum tests * musculoskeletal injuries that may prevent a reliable and safe assessment of the 1RM and RTF tests