Physical characteristics as predictors of quadriceps muscle isometric strength: a pilot study.

This one-group experimental study was carried out to investigate the relationship between isometric strength of quadriceps femoris muscle group and physical characteristics of subjects namely: age; weight; and height. Prediction equations were also derived for quadriceps isometric strength from these physical characteristics. Fifty volunteer, right-legged healthy normal male subjects participated in the study. They were aged between 19 and 27 years. The subjects had no previous history of neuromuscular and skeletal injuries to the lower limbs. Their ages, height and weight were measured in years, centimeters and kilograms, respectively. Quadriceps isometric strength was measured using an adapted cable tensiometer (ACT) and recorded in kilogramforce (kgf). Pearson's product correlation co-efficient (r) was used to study the relationship between quadriceps strength and each of age, height and weight. Linear and multiple regression analyses were also carried out. The result showed a high and positive Pearson's moment correlation coefficient (r) between quadriceps isometric strength and each of weight and height. A positive but low correlation (r) was also found between age and quadriceps isometric strength. Prediction equations were also derived from the linear and regression analyses. The study concluded that there was linear relationship between the physical characteristics and quadriceps isometric strength. It was recommended that the prediction equation be employed to estimate quadriceps strength while setting muscle strengthening goals in the clinics during medical rehabilitation for patients within the age range used in this study.