Sled drags provide a crazy quad pump and can do wonders for conditioning and leg growth, especially in those with back pain. They're also one of the most knee-friendly exercises.

How to Do It

  1. Pull your shoulder blades back and down. Make a big chest.
  2. Lean back to start the movement. Drive your heels into the ground.
  3. Take small steps backward, keeping the tension on the quads.

There are more cheap sleds on the market than ever, so it's hardly an excuse any more if your gym doesn't provide one. There are nylon sleds safe for gym floors and durable metal sleds costing $100 that you can drag up and down the street. A sled and some Craigslist weight plates are a worthwhile investment.

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