Are you spending hours at the gym, only to find minimal results?

You may be able to blame your parents: One in five people are born with genes that can affect your ability to burn fat by exercising, London’s Daily Telegraph reported.

Researchers at London University also found that regular exercise did little to prevent some medical conditions, like heart disease or diabetes.

Dr. James Timmons of the Royal Veterinary College at the University of London, who led the study, said these people would be better off focusing on alternate ways of staying healthy, like eating right and taking medications.

The study, which is published in the "Journal of Applied Physiology," looked at more than 500 participants who underwent aerobic training for 30 minutes each, five times a week.

Twenty percent of participants found their maximum oxygen increased by less than five percent, and 30 percent of participants were unable to increase insulin sensitivity.

An analysis of muscle tissue from this group proved they had a set of 30 genes that "predicted the increase in oxygen intake." Out of the 30 genes, 11 proved to have a specific impact on how much a person would profit from exercise.

Click here to read the full story at the Daily Telegraph.