Today, I'm excited to share insights from another recently pre-printed study on muscle growth. Last time, we covered the effects of hip angle in the leg extension on quadriceps hypertrophy. This time, we’re covering the idea of doing lengthened partials after hitting full range of motion failure.
A recently pre-printed study by Larsen et al (2024) looked at the effects of doing partials past failure versus ending the set upon hitting full range of motion failure in the calves.
Using a within-participant design, 22 untrained participants performed single-leg Smith machine calf raises for 10 weeks. The only difference in how the two limbs were trained was when the set was ended.
For one limb (plantarMF), the set was ended when the participant couldn’t get another full repetition, getting all the way onto their tippy-toes (yes, that’s the scientific term). For the other limb (dorsiVF), participants extended the set, just doing partials until they either couldn’t bear the discomfort anymore and hit volitional failure, or until they couldn’t even move out of the fully stretched position anymore.
Why did the researchers manipulate set endpoint? Well, calf raises are generally hardest at the very top of the movement. When you fail a set, it’s because you can’t quite “lock out” the calf raise.
In other words, the calf raise is an exercise that is hardest at short-muscle lengths, when the calf muscles are close to the fully contracted position. Since a substantial body of evidence now suggests that training a muscle at longer-muscle lengths might be better for muscle growth, we wanted to see whether doing lengthened partials past failure – when you’re unable to get a full rep – would also be better for building muscle than just using a full range of motion. Many people have been applying the research in this fashion.
The researchers measured increases in muscle thickness of one of the calf muscles, the gastrocnemius.
Hypertrophy of the medial gastrocnemius was slightly greater when performing lengthened supersets versus just full range of motion (around 40% greater). Importantly, the lengthened superset group also went past failure and accumulated greater volume load, making it difficult to tell whether the additional hypertrophy stemmed from the lengthened training, failure point, or overall volume load.
Interestingly, this is in line with previous findings by Kassiano and colleagues, who compared the effects of using a full range of motion, doing lengthened half-reps, and doing shortened half-reps on the leg press calf raise on gastrocnemius hypertrophy. For both the lateral and medial measurement site, lengthened partials led to the most muscle growth - around twice as much as just doing full range of motion. As you’d expect, shortened partials resulted in the least muscle growth.
Notably, lengthened partials led to around 100% more muscle growth, whereas lengthened supersets only led to an additional 40% muscle growth in the current study by Larsen et al. So, while we need a direct comparison of lengthened partials and lengthened supersets to be able to confidently answer the question, a tentative conclusion is that lengthened partials probably lead to at least as much or more hypertrophy than lengthened supersets.
That said, in light of the results from this study, lengthened supersets do likely still offer a hypertrophy benefit – at least in the context of the calf raise exercise and the gastrocnemius muscle. Based on the broader evidence landscape, my hunch is that this finding generalizes well to most muscles/exercises, particularly exercises that are most challenging in the peak contraction.
You might ask whether training the calves in the stretched position leads to more muscle growth. I suspect the answer is yes. A study by Kinoshita et al found that standing calf raises – with the knees extended, lengthening the gastrocnemius – led to more gastrocnemius hypertrophy than seated calf raises, which flex the knee, shortening the gastrocnemius. Our own lab, spearheaded by Brad Schoenfeld, found similar results in an as-of-yet unpublished study: substantially greater gastrocnemius hypertrophy from standing calf raises versus seated calf raises, and potentially slightly greater soleus hypertrophy from seated calf raises.
As far as your training goes, here’s how to apply these findings:
Takeaways:
- Doing some partials in the stretched position after hitting failure (what I like to call a lengthened superset) likely leads to more growth than just ending the set at failure, at least on a set-per-set basis. At the very least, that’s true of the calf raise exercise for the gastrocnemius; this probably generalizes to other muscles and exercises, but we can’t be too confident until we get studies examining this idea.
- If you don’t enjoy doing just lengthened partials, lengthened supersets could be a good way to increase the emphasis on the stretch and potentially see more muscle growth.
- Doing standing calf raises – or any calf raise with your knees extended – is very likely better for the gastrocnemius, since it stretches it more. For the soleus, since it doesn’t insert at the knee, any calf raise will work well, though there might be a very slight edge to a seated calf raise over a standing calf raise.
Recent Content
What Are The Best Exercises to Build Muscle?
In this video, Milo breaks down the science on which exercises might be best for building muscle. He talks about the lat pulldown, dumbbell row, dumbbell curl, bench press, squat, and more.
Watch the video →
|
|
How Many Sets YOU Should Do For MAXIMUM Muscle Growth (ft. Dr Mike Israetel)
In this video, Pak sits down with Dr. Mike Israetel of Renaissance Periodization and discusses the concept of volume volume cycling for hypertrophy.
Watch the video →
|
|
|
SBS Battle Royale
In this podcast episode, Greg, Pak, and Milo enter the impromptu-debate arena. Mental gymnastics, science, drama, and the signature SBS banter you all know and love are all packed into a pilot episode that will either be remembered forever or forgotten in a few weeks.
Listen now →
|
That's it for today's newsletter. Remember to subscribe to the SBS YouTube for a new video this Friday. Then, we'll be back with a new podcast episode next week, and another edition of this newsletter in two weeks.
Have a great rest of your week.
|
|
The SBS Team
Greg, Pak, Milo, and Lyndsey
|