Studies on the relationship between intensity of activity and entheseal changes (EC) have usually focused on the upper limb. Body size may bias lower limb EC, and thus evaluation of activity intensity may not be applicable. We study the effects of age, body size (as femoral length and femoral head superoinferior height) and intensity of physical activity on the lower limb EC. Our study sample (Helsinki) represents early 20th century Finns where age, sex and occupation are known for the individuals. Due to small number of females only males were included in this study. Based on the reported occupation, the material was divided into heavy (N = 17) and light (N = 6) activity groups. Entheses were observed for ruggedness, and the obtained scores were transformed into binary variables. Intensity of physical activity did not result in differences in EC in the lower limb. Surprisingly, also body size as femoral maximum length and femoral head height did not affect lower limb entheses. Age, a significant biasing factor in the upper limb EC, resulted in changes in some lower limb entheses. This was similar for left and right sides. Our results indicate that there are factors other than size, age and labour intensity affecting EC in the lower limb. Thus, the use of lower limb EC in activity reconstructions is problematic. However, our sample size was small which restricts the generalization of the results. Copyright © 2012 John Wiley & Sons, Ltd.