Take up rowing or kayaking. Doing a sport that activates your arm muscles will help you to tone your arm muscles. Consider taking up an arm focused hobby like rowing or kayaking, which requires arm strength and good core engagement. You can start by doing the rowing machine at the gym and then work up to taking classes in rowing or kayaking. You can also join a recreational rowing team in your area to get better at rowing and be more active on a weekly basis.
In a high plank position—palms flat on the floor beneath your shoulders, arms straight. Ease down on to your left forearm. Then, ease down your right arm until you’re in a forearm plank. Now push up with your right hand and then your left to return to a high plank. Repeat, alternating which side you lower first with each rep.” Lagree recommends doing two sets of ten reps. Another workout worth trying: these 9 resistance band exercises that will work your entire body.