PREDICTION OF ONE REPETITION MAXIMUM LOAD BY TOTAL AND LEAN BODY MASS IN TRAINED AND UNTRAINED MEN

Abstract

Introduction: One  repetition  maximum  test  (1RM)  is  often  used  to  evaluate  muscle  strength  and  to  prescribe  the  in ⴀ tensity  of  strength  training. However,  the  determination  of  the  initial  test  load,  and  duration  of  the  test  make  difficult  to  use the  same  in  non ⴀindividualised  environments. Objective: To determine coefficients to estimate the maximum strength (1RM), based on the relationship between muscular  strength,  lean  body  mass  and  total  body  mass. Methods:  Twenty ⴀeight  strength ⴀtrained  and  non ⴀstrength ⴀtrained  men  participated  in  this  study. Muscle  strength  was determined  using  the  1  RM  test  in  the  bench  press,  supported  barbell  row,  45°  leg  press  and  squat  exercise,  while  body composition  was  measured  using  the  skinfolds  method. After  verifying  the  correlations between  muscular  strength  and  body mass  and  composition,  the  coefficients  to  predict  the  maximal  strength  were  calculated  by  dividing  the  value  of  the  1  RM by  the  total  body  mass  and  lean  body  mass  (kg)  and  by  linear  regression  equation  based  in  these  parameters. Results: Significant  correlations  were  found  between  body  mass  and  lean  body  mass  with  muscular  strength  in  all  the exercises  ( r  =  0.47   ⴀ  0.76, P  <  0.05).  The  greatest  correlations  were  observed  between  the  muscular  strength  values  and lean  body  mass. There  was  a significant  difference  between  the  coefficients  obtained  from  trained  and  non ⴀtrained  subjects in  all  the  tested  exercises  ( P  <  0.05). Conclusions: The  results  suggest  that  the  coefficients  of  prediction  of  the  1RM  should take  into  account  the  body composition  and  the  training  status  of  the  individuals.