Make every day an opportunity to help him grow stronger. A few simple ideas are all it takes.
Getting stronger is hard work. Let your little guy know how proud you are of his accomplishments, and help him along by giving him the nutrition he needs when he's hungry from all the toddler exercises.
Large Muscle Activities
Start smooth, and then go bumpy. Keep him on a smooth, level surface until he learns to walk. Then take him into the yard or on the beach.
Investigate the stairs together. Only do this when you can be there to help. Otherwise, use a baby gate to block the way.
Walk his toy. Go for a walk with his pull toy.
Chase bubbles. Or chase each other.
Small Muscle Activities
String large beads. Or run small cars on a train track.
Fold clothes together. Try to, anyway.
Read books. Let him hold the book and turn the pages when you're ready.
Push buttons. Many toys have pretend buttons, like phones, remotes and cash registers.
Play outside. Explore sidewalk chalk or packing sand into a mold.