This study was carried out to investigate how age and gender influence hamstring-quadriceps (knee flexor-extensor) muscle strength ratio in a Nigerian urban population. One hundred and fifty apprently healthy male and female subjects in 3 age groups (group I, 11-20 years; group II, 21-40 years and group III, 41-60 years) participated. The hamstrings and quadriceps isometric muscle strength of all the patients was measured and their ages were recorded. The hamstring-quadriceps strength ratio for each subject was also calculated. The results showed that the hamstring muscles of the subjects have a strength that is about half the strength of the ipsilateral quadricepsfemoris muscle in each of the groups. A comparison of hamstring quadriceps muscle strength ratio across the age groups releaved no significant difference among both male and female subjects (p>0.05). No significant gender difference was found among the subjects in the age groups 11-20 years and 41-60 years (p >0.05) but in the age group 21-40 years the male subjects had a significantly higher Hamstring Quadriceps strength ratio than their female counterparts (p <0.05). It was concluded that age has no effect on hamstring/quadriceps (kneeflexor! extensor) strength ratio, whether in female or male individuals, and that male and female variation is related to a sense of competitiveness, societal achievement expectation and propensity to display prowess.
Key words: muscular strength, hamstring/quadriceps strength ratio, age and sex.