Affiliations: [a] Physiotherapy Department, Obafemi Awolowo University
Teaching Hospitals Complex, Ile-Ife, Nigeria | [b] Physiotherapy Department College of Medicine,
University of Ibadan, Nigeria
Abstract: Background and objective: Identifying methods of accurately
predicting endurance capacity of the back extensor muscles is of immense value
to both patients and clinicians. This study aimed to develop a multiple
regression equation using demographic and anthropometric measurements to
predict back endurance and to investigate the association between performed
back endurance results and back endurance predictions. Materials and methods: 376 healthy women and men aged 21–62 y
were recruited consecutively. All participants underwent the
Biering-Sørenson test of Static Muscular Endurance. Height and weight were
measured using standard procedures. Percentage body fat was estimated using
bioelectrical impedance analysis. Body mass index, lean body mass and body fat
mass were calculated. Based on these a regression model was used to generate
predictive equation for endurance time. Results: The final regression model which included demographic
and anthropometric variables could account for 43% of the variability in
back muscle endurance. Pearson's product correlation coefficient for the
association between performed static endurance and the predicted endurance were
(r = −0.129; p = 0.074) and (r = 0.671; p = 0.000) for male and female
participants respectively. Paired t-test showed significant difference (p =
0.000) between the performed static endurance and predicted endurance among the
male participants but not among the female counterparts (p = 0.959). Endurance
time of males (119 ± 49.8 secs.) was significantly greater (p = 0.014)
than that of the females (106 ± 47.6 secs.). Conclusion: Regression equation seems to be moderately valid
in predicting endurance time of the back extensors among females only. We
conclude that simple anthropometric measures cannot accurately predict back
endurance without significant errors. The larger error of prediction obtained
for the male participants could be indicative of an increasing influence of
motivational/psychosocial factors that are known to be independent of motor
ability in physical performance testing.
Keywords: Static endurance, back extensor muscles, Sørenson test, endurance time, predictive equation
