If used incorrectly, treadmills can pose safety risks to users, particularly for those with older, more fragile bodies. Before any workout, make sure you do a slow, minimum five minute warm up that increases in difficulty to get your muscles warm and your blood flowing. While there is no easy guideline for how fast a 70 year old senior should walk on a treadmill, we recommend you increase your speed to a pace that is comfortable for you and maintain consistency. When you are finished, gradually ease off the pace and complete a cool down routine to prevent injury.