You don't need a lot of equipment, dumbbells or a gym membership to weight train. Simply use your own body weight! Pushups, pull-ups, many yoga poses and squats are examples of weight bearing exercises. A simple web search for "weight bearing exercises" or "strength training without weights" will give you lots of info and inspiration.
Sit with your knees bent; feet flat on the floor ~ hip-width apart. Extend your arms straight in front of you, palms up. Your back should be straight, your chest up (a). Brace core, curl tailbone under, slowly lower upper body to 45-deg angle. At the same time, bend arms to bring elbows close to body, closing hands into fists and pulling them toward shoulders at eye level (b). Pause, then reverse the motion to return to start. That's one rep.
Try these yoga poses that will tighten and tone your core. Build muscle in your abs with these simple exercises you can do at home during a workout or before bed. Get the abs you want with these amazing yoga poses.