With body weight exercises, you can use your own weight to create resistance that builds strength.
Strength Training at Home: Workouts With and Without Equipment
20 Ways to Double Your Strength and Lift More Than Your Bodyweight
You Can Do This 10-Minute Workout at Home With No Equipment - The New York Times
10 Best Upper Body Bodyweight Exercises
The 9 Best Lower Body Strength Training Exercises
How Much Should I Be Able to Deadlift? - Gunsmith Fitness
Body-weight workout – part 2
Here's how to get stronger by using just your own body weight
Exercises With 5-Pound Dumbbells
Who can lift twice their own body weight? - Quora
19 Bodyweight Exercises to Build Strength
5 Best Exercises for a Full-Body Workout