A study from the Cambridge Centre for Sport & Exercise Sciences found that an individual's genetic traits can significantly affect the outcome of athletic training. In order to better understand how genes affect muscle strength, cardiovascular fitness, and anaerobic power, 3,012 adults aged 18-55 were surveyed. Each individual had not been previously exposed to exercise training. During the study, each participant was subject to the exact same training regime, though diet, nutrition, recovery, and injuries varied. The researchers discovered that genetic differences are responsible for 72% of the outcome variation for people following identical exercises designed to improve muscle strength. Meanwhile, genetic variations caused 44% of the differences seen following cardiovascular fitness exercises, measured through VO2max testing, and 10% of the differences in outcomes following exercises to improve anaerobic power. In total, the study identified 13 genes, and associated alleles, as being responsible for how well the body reacts to cardiovascular fitness, muscular strength, and anaerobic power exercises. If specific genes show a correlation to increase the effectiveness of specific exercises and training regimens, then training and recovery programs could be designed to fit an individual's needs. A training program allowing for personalized design could prove beneficial for physical therapy patients, athletes, people trying to lose weight, and much more.