Do you travel a lot? If so, you may find it difficult to keep up with a strength-training program that relies primarily on gym equipment. What you need is a handful of basic resistance exercises that require no weights. Here are four moves that you can do in a hotel room-and that cover most of the major muscle groups from head to toe:

  1. PUSH-UPS. Great for your chest, shoulders and triceps.
  2. AB CRUNCHES. Abdominal crunches are a bit easier with your feet up on a chair and legs bent at a 90-degree angle. If there's no chair in your room, do the crunches with your feet flat on the floor and knees bent.
  3. SQUATS. An all-in-one workout for quadriceps, hamstrings and glutes (thighs and butt). Be sure to pay attention to form: You should squat down only until your upper thighs are parallel with the floor, and not any farther than that.
  4. CALF RAISES. Probably the easiest calf-toning exercise around. Standing up, simply push up on your toes, and then return your heels to the floor.

Depending on your fitness level, do one to three sets of each exercise. Each set should have 8 to 12 repetitions.