For last few days Mother is feeling tired after doing any outdoor walking such as getting grocery or even walking. Weight is 72-73 and has been same for last 1 year. She is not coughing or doenst have breathlessness but there is fatigue every time she goes for getting grocery or waking outside. She even got tired after taking bath and coming out of bathroom. But for normal indoor work such is cooking or dusting or doing pranayam there is no such issue. What could be the reason. Any tests that she should take.