Don’t Plan On Taking the Stairs
Single-joint leg extensions are a common way to complete your leg workout, but turn up the intensity by doing a century set.
By Bill Geiger, MA
The Plan of Attack
Bodybuilders love to give it everything they’ve got as they finish off a particular bodypart, but nowhere is this mentality more evident than on leg day, when a brutal workout is easily measured by your inability to even pick your feet up off the ground. If you can walk away from your last set without some obvious discomfort, you’re simply not working hard enough. While leg extensions are an obvious choice to finish off the quads — most other front thigh exercises are multijoint moves, and leg extensions are single joint — to really deepen the burn consider skipping the straight-sets approach. Forced reps and drop sets are both good, but here’s a technique you’ve probably never tried that works on your very last set. You’re going to do just a single set of 100 reps.
One Set of Pure Hell
Start by doing your normal 2–3 sets. At the top of the rep, the point of peak contraction, squeeze and hold it there for a count. Focus on feeling the muscle work on each rep, not racing through your set.
On your last set, select a weight that’s about 25% of what you can do for 10 full reps (your 10RM). Do as many reps as you can under control. If you can’t reach 100 reps, you can take a short break, but the length of the break in seconds is only equal to the number of reps you are short of 100. So if you did 80 reps, you get only a 20-second rest period before you must start up again.
Adjust the seatback so that your knees sit just off the edge of the bench. The padded bar should sit just above your ankles. Sit squarely in the apparatus, holding onto the handles to keep your body stabilized.
Feel the Burn
1) Selecting the right weight is crucial because you’ll never make it to the end if you go too heavy. Start by figuring out what weight you can do for 10 and only 10 reps. So if you can do 185 pounds on the machine and can just reach 10 reps, start with that figure. Now compute 25% of that weight. That’s your working weight for century sets — about 45 pounds in this case. We know it doesn’t sound heavy, but it will be soon.
2) After you finish your previous set, rest about 90–120 seconds and begin your century set. Use a smooth and controlled motion, squeezing your quads very briefly at the top and lowering under control. The weight stack shouldn’t touch down between reps.
3) Do as many reps as you can; you’ll probably feel the burn start to magnify at about 50 reps, but keep going as long as you can. Say you complete 65 reps and have to stop — that’s fine — you get a 35-second break (100 minus 65), at which point you must start the set again. Do as many additional reps as you can, again taking a break for only as many seconds as you have left till you hit 100 reps. Continue in this manner till you reach 100.
Focus on Fibers
An exercise in which you try to achieve 70 or more reps is clearly one that activates the slow-twitch muscle fibers (those are the fibers that are more efficient at using oxygen), which really haven’t been all too active in your leg workout thus far because most bodybuilding-type training is done for fast-twitch fibers. But as those slow-twitch fibers start to become exhausted, the fast-twitch fibers (the ones most likely to grow) are increasingly recruited, so now you’ve attacked both types of fibers in a single set and are primed for growth.
Keep Feet Flexed Up
Your toes should be pointing toward you — not pointed away — for maximal quad activation.
Take It to the Top
Fully extend your legs, and make sure you go all the way down so you’re not doing partial reps.