After many years of running, working with several very different coaches, I eventually concluded that the precise details of an interval workout – the exact number of reps, distance, recovery time, and so on – don’t really matter. As long as you’re doing a reasonable workout, what really matters is how you run it.
Strength training has many of the same debates, perhaps even more complex and convoluted. How many reps and sets should you do? How heavy should the weight be relative to your max? How quickly should you perform the motion? How long should you rest? It’s all a bit daunting for someone who just wants to build and maintain a reasonable amount of muscle mass. That’s why I’m a fan of some recent research by McMaster University muscle researcher Stuart Phillips that suggests that, like running, the details matter less than your effort.
Phillips originally published a paper back in 2010 showing that lifting to failure at 30 percent of one-rep max (the subjects averaged 24 reps per set) produced the same amount of muscle protein synthesis as lifting to failure at 90 percent of one-rep max (an average of five reps). Not surprisingly, people were skeptical.
Since then, he’s followed up with several more studies, and presented his most recent results at a conference last month:
[…] The new results, which were presented at York by Phillips’s graduate students Robert Morton and Sara Oikawa, put 49 well-trained volunteers through a vigorous full-body training routine, four times a week for 12 weeks. Half of the subjects performed a standard workout protocol of three sets of each exercise, with a load chosen to induce failure after between eight reps and 12 reps a set. The other half did the same program, but with a lighter load chosen to induce failure after 20 reps to 25 reps a set.
Most of the subjects were current or former athletes, including national-level athletes and power-lifters. “These were very big guys,” Morton says. Despite their extensive training history, the subjects still managed get stronger, add muscle and reduce body fat, with no statistically significant differences between groups. […]
Now, it’s important to point out that no one, including Phillips, is suggesting that there are no differences between the two routines. The principle of training specificity still applies, so if you want to be a powerlifter, you should still train by lifting a very heavy weight a few times, rather than a light weight many times.
But it’s a question of emphasis. Don’t get hung up on the details of your workout program, or on the availability of the “right” equipment to provide the “right” load for your muscles, because the most important element is the need to push to failure, or at least near-failure, where you can’t do another rep.
For example, I’m doing mostly bodyweight exercises these days, and this tells me I don’t need to worry too much about the fact that I can do significantly more pushups than dips, and more dips than pull-ups. As long as I’m doing each exercise to failure, I’m in business. As Phillips says, “I estimate that the difference for most mere mortals would be absolutely inconsequential from a health and fitness standpoint.”