Prediction of one-repetition maximum from submaximal ratings of perceived exertion in older adults pre- and post-training.
BACKGROUND
Individual's one-repetition maximum (1-RM) is required to calculate and prescribe intensity for resistance training, while testing protocols enhance the risk of injuries and are time-consuming.


OBJECTIVE
The aim of the present study was to assess the accuracy of 1-RM prediction from ratings of perceived exertion (RPE) of resistance exercises performed at submaximal sets (intensity and volume) in older adult males before and after a 12-week rehabilitation program.


METHODS
18 untrained subjects (70.4 ± 4.5 years) first completed a 1-RM direct assessment with a horizontal leg press pre- and post-training. Thereafter, participants performed, in a random order, 2-repetition sets with loads unknown to them (corresponding to 20, 45 and 70 % of 1-RM). The RPE was recorded immediately after the sets. That RPE associated to its corresponding load was subjected to a linear regression analysis to extrapolate the maximal RPE score and its corresponding 1-RM.


RESULTS
RPE and relative intensities of sets appeared related pre- [r (2) = 0.59, standard error of estimate (SEE) = 13.3 %] and post-training (r (2) = 0.83, SEE = 8.1 %). Differences between measured and predicted 1-RM were reduced from the beginning to the end of training but standard deviations remained high (17.4 ± 11.8 vs. 4.2 ± 11.1 kg). Pre-training, 1-RM expressed relatively to body weight was negatively related with the errors of 1-RM predictions (r (2) = 0.39, p = 0.03).


CONCLUSIONS
In older subjects, RPE may be used to predict 1-RM; however, the predicted value deviates considerably from the measured one, necessitating cautious application. Importantly, this method allows to capture training-induced change in 1-RM, thus making possible assessing training's effectiveness and allowing its modification if necessary.
Institut de Recherche bioMédicale et d'Epidemiologie du Sport (IRMES), Institut National du Sport de l'Expertise et de la Performance (INSEP), Paris, France. francois.desgorces@parisdescartes.fr.|Université Paris Descartes, Sorbonne Paris Cité, EA 7329, Paris, France. francois.desgorces@parisdescartes.fr.
François-Denis
FD
Desgorces
Institut de Recherche bioMédicale et d'Epidemiologie du Sport (IRMES), Institut National du Sport de l'Expertise et de la Performance (INSEP), Paris, France.|Université Paris Descartes, Sorbonne Paris Cité, EA 7329, Paris, France.|Université Paris Est, Marne-la-Vallée, France.
Rémi
R
Thomasson
Institut de Recherche bioMédicale et d'Epidemiologie du Sport (IRMES), Institut National du Sport de l'Expertise et de la Performance (INSEP), Paris, France.|Collegium of Sciences and Technology, Université d'Orléans, Orléans, France.
Shehrazad
S
Aboueb
Institut de Recherche bioMédicale et d'Epidemiologie du Sport (IRMES), Institut National du Sport de l'Expertise et de la Performance (INSEP), Paris, France.|Université Paris Descartes, Sorbonne Paris Cité, EA 7329, Paris, France.|Centre d'Investigation en médecine du Sport, Hôtel-Dieu, Assistance Publique-Hôpitaux de Paris, Paris, France.
Jean-François
JF
Toussaint
Institut de Recherche bioMédicale et d'Epidemiologie du Sport (IRMES), Institut National du Sport de l'Expertise et de la Performance (INSEP), Paris, France.|Université Paris Descartes, Sorbonne Paris Cité, EA 7329, Paris, France.
Philippe
P
Noirez
D000368:Aged; D000375:Aging / Q000502:physiology / Q000523:psychology; D061827:Dimensional Measurement Accuracy; D004192:Discrimination, Psychological / Q000502:physiology; D015444:Exercise / Q000502:physiology; D005080:Exercise Test / Q000379:methods; D006801:Humans; D008297:Male; D005082:Physical Exertion / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D011897:Random Allocation; D055070:Resistance Training / Q000009:adverse effects / Q000379:methods; D020379:Risk Adjustment / Q000379:methods; D055948:Sarcopenia / Q000517:prevention & control*; D016896:Treatment Outcome; D014947:Wounds and Injuries / Q000209:etiology / Q000517:prevention & control
Aging; One-repetition maximum; Perceived exertion; Rehabilitation; Strength training