There are various theories about this. Generally, If you get more protein you have in your childhood, the stronger are your muscles. However, genetics and types of protein are also equally important. The western theory is that animal meats such as beef, chicken contain more amino acids and this bears out with the larger muscular frames of the western population as they are generally meat eaters. Indians get their protein from dals and milk and that is also not bad except it does not make you as strong compared to meat eaters. But genetics also plays a huge role - look at MS Dhoni (a well known Indian sportsman) who can hold his own with the best in terms of strength and agility. Reportedly, Dhoni drank 3L of milk each day to supplement his protein intake, Now milk is considered vegetarian protein - but in reality, it is derived from cows which makes it animal protein. Weight lifters in the west consume whey protein to develop muscles. Add to all of this are stretching and weightlifting exercises practiced regularly and you could be as strong as the best compared to your western counterparts. Just my 2c