Sex difference may also influence the effect of exercise.218 It has been demonstrated that female mice developed greater increase in physiological myocardial hypertrophy after treadmill or voluntary wheel running.219 Moreover, although both male and female mice showed an increase in left ventricular mass after treadmill running, male and female mice had different regulation in Akt and MAPK signaling pathways in response to exercise.220 Further study is required to determine sex-specific signaling pathway responses upon exercise.221. The gene discussed is AKT1; the disease is cardiac hypertrophy.