Just as NASCAR drivers rarely turn right, bodybuilders seldom know when to take their foot off the gas. And honestly, who could blame us? We know that to enhance the size, shape and symmetry of our muscles, we have to take our training to the extreme, and going mach 2 is the only gear that makes sense. But truth be told, there are times when downshifting just a bit toward the end of the workout can make a lot of sense.
Two Steps Back
The idea of a back-off set is pretty much exactly how it sounds: After you’ve pounded the muscle with heavy weight and serious intensity, you back off slightly on the weight that you can do for slightly more reps.
Before you say anything, we’re not talking drop sets. A drop set has you doing a set and quickly decreasing the weight by about 25% and immediately resuming the exercise without rest. A back-off set, however, uses the same rest periods between sets as you typically would, but you’re following your most intense (heavy) sets with a less intense one.
One important point about back-off sets is that they need to be preceded by heavier, more intense sets. Those preliminary sets are the bread and butter, the ones that best target the fast-twitch muscle fibers, which are the fibers for strength and size. But back-off sets hit those fibers in a different way than the heavy sets.
For starters, when you back off the weight, you automatically improve your form. You don’t have the necessity to cheat or use body english, so your target musculature is as active as possible. You automatically cause them to work simply by making them do the work on their own without the use of momentum. The better able you are to manage the weight, the easier it is for you to focus on the peak contraction of each rep and provide constant tension throughout the set.
Make no mistake, even though you’ve downshifted, during a back-off set you also continue driving water, blood and nutrients into the cells, and that’s important because training produces waste products in the muscle cells — the result of burning glucose and fat to fuel muscular contractions. During a back-off set, that waste buildup continues to draw water inside muscle cells, and like a balloon, the more water the muscle cell can hold, the bigger the pump you’ll experience. The pump that ensues via the back-off set essentially stretches the muscle cell, making the muscle itself temporarily bigger while initiating biochemical pathways that prompt permanent growth.
Another advantage of doing back-off sets is that it can help prevent overtraining (by substituting a heavy set with a slightly lighter one) while also allowing your muscles to be exposed to varying loads, intensities and stimuli. As you know your muscles respond to varying types of resistance. For size, you focus on weight that allows you to fail in 8–12 reps. If you do an exercise for heavy sets of say 6–8 reps, for example, a back-off set of 10–12 reps allows you to target those muscle fibers in a slightly different manner because you’re using a different relative intensity. If you did a back-off set with a really light weight, say for 20 reps, you’d also be calling into play the slow-twitch fibers, which thus far have been fairly inactive.
How much weight should you back off? That probably depends on the individual, and how you did on your previous sets. If you did heavy sets and used intensity-boosting techniques, you may already be highly fatigued, so dropping the weight by 10% may not allow you to do any more reps.
On the other hand, someone who doesn’t train past failure may have fuel left in the tank, so a 10% drop in weight might see an increase of 2–4 reps. In general, you want to do a back-off set such that you can do 2–4 more reps than you did on your previous ones, but like we said, there are times you might want to really flush the muscle and do a very high-rep set. That increase in reps may indicate a 10–20% decrease in weight, but base the amount on personal experience and your training goals.
Here’s an example of what a routine consisting of back-off sets looks like on chest day. The back-off set falls on the last set of each exercise (or even just a couple of exercises). Select a weight that’s lighter than your previous working sets to cause failure at the target rep range.
Incline Barbell Press 4 Sets x 6, 6, 6, 10 Reps
Flat- Bench Dumbbell Press 3 Sets x 8, 8, 10-12 Reps
Decline Machine Press 3 Sets x 8-10, 8-10, 12-15 Reps
Cable Crossover 3 Sets x 12, 12, 15 Reps