Driving with your arm out of the window
While it may feel comfortable and familiar to rest your arm out of the window of your car, the truth is that this is an unnatural position for your arm to be in for long periods of time. This could lead to developing tendonitis. Try and keep your arms inside of the car and in a position that doesn’t leave your joints feeling any sort of stress. Also, if you exercise, try and engage in some low-impact workouts to give your joints a break.