1. Place your feet on top of a bench. You can also do these on a chair, couch, or park bench. Anything just above knee height will work.
2. Have your hands on the floor in front. You may also choose to use your elbows instead if it's more comfortable, but this will also change your body angle and overall feel of the exercise.
3. Start with your hips up in a pike position. This will test your tight hamstrings and act as a good dynamic stretch.
4. Keep your toes on the bench and drop your knees towards the floor without letting them touch the floor fully. If they do, you'll likely need a higher bench (or couch). Just place something on top of it to add height.
5. As you extend your knees raising your hips again, squeeze your quads like you would in a leg extension machine. If your bodyweight isn't difficult enough, then use a band to add resistance.
6. For the more advanced banded version, just loop the band behind your knees and keep your hands clamped down. Shorten the band if you need more resistance.

• You can do these one leg at a time to challenge your single-leg strength.
• To focus more on eccentric strength, try raising up with both legs and lowering with one, with or without a band.
• If hamstring length is an issue then these can also be done in a plank rather than pike position to finish. For the plank leg extension, just imagine pushing yourself forward and away from the bench, as opposed to pushing your hips up.

There are multiple benefits beyond just getting a quad pump. The pike on a Swiss ball also produces some of the greatest levels of muscle activation for both upper and lower abdominal fibers. If you don't have a stability ball, this equipment-free version could be your next best option.

The pike is a real challenge for your hamstrings... more than it should be for some! Starting your heavy leg workouts with a few sets of these will help get some length through your hamstrings while also activating your core and quads. As a warm-up, there's no need to go to failure.

Primarily, this is a quadriceps exercise. You could see it as a direct replacement for the leg extension machine, although arguably a little more knee-friendly for those with preexisting crankiness.

If leg extensions, sissy squats, and such are out of the question, these are a good alternative. They'll help you get a pretty good quad stretch at the bottom, while emphasizing their shortened position at the top. Adding the band increases the tension as your knee is further extended.

Use pike leg extensions as a pre-workout mobility exercise done at a relatively low intensity, or as a hard-hitting way to isolate your quads while working your abs at the same time.