This is the best rep tempo for MAXIMUM gains

Summary

Highlights

• The study involved endurance-trained individuals performing barbell squats. 🏋️‍♀️
• A comparison of 1-second vs. 4-second eccentric tempos was analyzed. ⏳
• Total muscle growth showed no significant difference between the tempos. 🤷‍♂️
• Vastus Lateralis showed greater growth in slower reps, but not everywhere else. 🤔
• Previous research echoes similar findings about eccentric speeds and muscle growth. 📚

Key Takeaways

• Whether you go fast or slow, the total quadriceps muscle growth is similar. 🚶‍♂️💪
• Evidence suggests moderate control during eccentric phases is key to boost strength. 💪
• Don’t stress over the perfect rep tempo; your personal comfort matters most. ✌️
• Slower eccentrics showed more growth in Vastus Lateralis, but it could be a fluke. 🤔
• Focus on what feels right and natural for your gym routine. 🏋️‍♂️

Overview

Chapters

• 00:00 - 00:30: Introduction to Repetition Tempo The chapter titled 'Introduction to Repetition Tempo' explores the optimal repetition tempo for gaining muscle and strength. It discusses the popular belief, largely spread by influencers on YouTube, that the best approach involves performing the eccentric phase of a lift slowly and the concentric phase explosively. The chapter introduces a new study that examines the specific impact of different eccentric phase durations during barbell squats.
• 00:30 - 01:00: Study on Eccentric Durations in Squats In this chapter, a study is explored where two groups were compared based on different eccentric tempos during squats. One group used a 1-second eccentric phase while the other used a 4-second eccentric phase, with all other variables kept constant, including the load, training frequency, and training to failure. The research aimed to analyze the impact of eccentric tempo on muscle hypertrophy and strength. Additionally, it is noted that participants were endurance trained but not strength trained.
• 01:00 - 01:30: Participants' Background and Main Findings This chapter discusses the background of participants and the primary findings from a study. Participants, who were part of an academic curriculum, engaged in 6 to 8 hours of cardio exercise weekly but did not engage in strength training. The study lasted 7 weeks, which the author notes as somewhat short. The primary finding was that there was no significant difference in quadriceps muscle growth between the groups studied. This aligns with a 2022 review that similarly found supporting evidence for eccentric contractions.
• 01:30 - 02:00: Optimal Eccentric Duration for Performance This chapter discusses the effect of eccentric duration on concentric performance and strength development. It suggests that a 2-second eccentric duration may enhance subsequent concentric performance without negatively impacting strength development. The chapter notes that there is no clear difference in hypertrophic response and strength gains when using eccentric tempos between 2 to 6 seconds. Excessively slowing down eccentric phases may be detrimental to strength and has no significant impact on muscle growth.
• 02:00 - 02:30: Eccentric Tempo and Muscle Growth The chapter 'Eccentric Tempo and Muscle Growth' explores the relationship between repetition tempo and muscle growth. It starts by explaining that glycogen depletion and muscle fatigue levels are similar in both type one and type two muscle fibers, regardless of whether the repetitions are done quickly or slowly, as long as the endpoint is reached. This means muscles perform the same amount of work, leading to equivalent muscle growth. However, a specific study highlighted a curious finding in the Vastus Lateralis, a muscle in the quads, where greater muscle growth was observed, suggesting nuances in how tempo can affect muscle development.
• 02:30 - 03:00: Study's Curious Findings on Vastus Lateralis The chapter discusses a study's findings on muscle growth in the Vastus Lateralis, specifically focusing on the effects of slower eccentric training. The results indicated significantly greater muscle growth in this specific region for the group undergoing slower eccentric training. However, the interpretation of these results has been debated. While some assume that slowing down eccentrics leads to greater muscle hypertrophy overall, the study did not find significantly greater growth in the entire quadriceps or in other measured muscle regions. The chapter suggests that the observed growth in the Vastus Lateralis might be a result of a statistical anomaly, also known as a Type I error.
• 03:00 - 03:30: Type I Error Explanation Type I error is explained as a false positive occurrence.
• 03:30 - 04:00: Measurement Errors in Studies The chapter discusses the concept of measurement errors in studies and highlights how these errors can skew results in favor of one group or direction. It explains the potential for bias or inaccuracies, especially in procedures like ultrasounds, which depend heavily on the operator's skill. The text also provides an analogy with DEXA scans to illustrate how minor discrepancies, like differences in arm growth between scans, can be overly scrutinized, emphasizing the importance of understanding and accounting for measurement errors in scientific studies.
• 04:00 - 05:00: Regional Hypertrophy and Study Limitations The chapter discusses the limitations of using single site measurements for assessing body composition and regional hypertrophy. It points out that while DEXA scans are reasonably accurate for estimating total body fat percentage across the entire body, they can still have a margin of error of a few percent. Moreover, at an individual level, DEXA scans are not ideal for tracking progress. Although they are useful in group analyses, they become less reliable when examining individual sites, such as comparing the left and right arms, due to their limited accuracy in small areas. Similarly, the use of ultrasound for measurements can lead to varied results depending on the number of measurements taken, indicating a need for caution in interpreting findings from such devices.
• 05:00 - 06:00: Comparison with Pearson et al. Study In this chapter, a comparison with the Pearson et al. study is made regarding muscle growth measurements across different groups. The discussion highlights the importance of looking at the total muscle growth rather than individual muscle figures, as the total measurement is found to be more reliable. The chapter argues that even though there might appear to be more muscle growth, the total growth was similar between groups. The concept of regional hypertrophy is introduced, suggesting that specific exercise phases might target certain muscle regions more, supported by research showing the vastus lateralis is particularly activated during the eccentric phase.
• 06:00 - 07:00: Discussion on Repetition Tempo's Impact The chapter discusses the impact of repetition tempo on muscles, specifically focusing on the quadriceps. It argues against the idea of regional differentiation in the quadriceps due to its simplicity in function, which is primarily knee extension. Unlike the hamstrings or deltoids, which exhibit substantial functional differentiation among different muscle heads, the quadriceps, particularly the Vastae muscles, do not allow for targeted, isolated training of individual heads due to their straightforward function.
• 07:00 - 08:00: Strength Development Findings The chapter titled 'Strength Development Findings' discusses the debunking of certain myths related to squatting techniques, specifically targeting the VMO (Vastus Medialis Obliquus) and achieving muscle hypertrophy through specific squatting styles. It highlights a lack of strong evidence supporting regional differentiation within quadriceps muscles, challenging the concept of targeted muscle development through varied squat positions. However, the chapter mentions that studies indicate slower eccentric speeds in exercises as beneficial. The findings suggest evidence supporting this aspect of training, although regional muscle growth measurement might contradict or support these assumptions. The discussion references a study by Pearson et al. to underline these points.
• 08:00 - 09:00: Mechanics of Stretch Reflex in Eccentric Phase The chapter explores the mechanics of the stretch reflex during the eccentric phase of muscle movement. The discussion begins with findings that suggest greater muscle growth with a faster eccentric tempo, which contradicts traditional theories. Theoretically, slowing down or controlling the eccentric phase should be beneficial due to increased strength during this phase. The absence of control in the eccentric phase leads to no muscle contraction, ignoring mechanical muscle tension gains. However, these are theoretical considerations, and the practical applications could vary.
• 09:00 - 10:00: Comparison with Shibata et al. Study In the chapter "Comparison with Shibata et al. Study," the focus is on examining empirical data from the Pearson study, which explores the impact of eccentric duration on muscle gains. The study compares leg extensions performed with a 1-second versus 3-second eccentric duration. Findings reveal that while the 1-second group experienced more significant gains in the distal quadriceps, overall quadriceps size and strength improvements were similar across both groups. The chapter highlights the importance of considering total muscle changes and the broader research landscape, which generally finds little effect of repetition tempo on muscle hypertrophy.
• 10:00 - 11:30: Interpreting Findings in Broader Research Context This chapter discusses the importance of interpreting research findings within the larger context of existing studies. It highlights the value of expert guidance in navigating through vast amounts of information in the field of fitness and health, and promotes an online PT Certification course designed to help individuals gain a comprehensive understanding of topics such as muscle growth, fat loss, strength development, and health sciences. The course aims to provide practical and effective strategies to enhance personal fitness outcomes.
• 11:30 - 12:30: Practical Advice on Repetition Tempo The chapter titled 'Practical Advice on Repetition Tempo' introduces training methods used by coaches for a range of clients, including general population and professional bodybuilders. The chapter offers a PT toolkit consisting of calculators, case studies, guides, an exercise library, and discounts on partner products and services. Emphasizing credibility, it encourages checking student reviews, boasting high satisfaction scores. It transitions back to discussing a study on strength development, hinting at significant findings related to a 4-second tempo.

This is the best rep tempo for MAXIMUM gains Transcription

• 00:00 - 00:30 What is the best repetition tempo for maximum gains? Based on most influencers on YouTube I get the impression that the consensus view is: Relatively slow eccentric, meaning you lower your weights relatively slowly, the lengthening phase is performed slowly, then you do the concentric phase, the shortening phase, the lifting phase rather explosively. A new study looked at this, so let's dig in. The researchers specifically looked at the effect of the eccentric durations, or the lowering phase, of barbell squats.
• 00:30 - 01:00 One group squatted with a 1 second eccentric tempo, and the other group squatted with a 4 seconds eccentric tempo. The load was the same, they trained the same frequency, and they trained to failure, so all else was equal. One group did more faster repetitions and the other group did fewer slower repetitions, allowing us to investigate specifically the effect of the eccentric speed on muscle hypertrophy and strength development. An interesting little factoid about the study is that the subjects were endurance trained, but not strength trained. In fact, they were highly endurance trained.
• 01:00 - 01:30 The researchers noted: “As part of their normal academic curriculum, participants engaged in 6 to 8 hours of low to high intensity exercise per week.”, but they were specifically not strength trained, so they were basically doing 6 to 8 hours of cardio per week. I don't know for what study that's “normal academic curriculum”, but I don't want none of that. The main finding was that after the 7 week study, which is a little bit short, there was no significant difference in total quadriceps muscle growth between the groups. This finding is in line with a previous 2022 review, which concluded that: “Overall, evidence supports eccentric contractions below
• 01:30 - 02:00 2 seconds duration to improve subsequent concentric performance...” So they recommend not decreasing your eccentric speed too much to improve strength development, we'll get to the strength development of this study in a bit more detail later, and they continued: “...There is no clear difference between using eccentric tempos of 2 to 6 seconds if the aim is to increase hypertrophic response and strength.” So basically they said that if you slow your eccentric phases down a lot it might hurt strength development And it doesn't have any effect on muscle growth. Some research has also found that,
• 02:00 - 02:30 mechanistically speaking, we get to the same level of glycogen depletion in type one and type two muscle fibers regardless of our repetition tempo, provided we get to the same endpoint. So you can do more faster repetitions or fewer slower repetitions. You get to the same level of muscular fatigue in the end and therefore the muscles are doing the same amount of work and therefore you get the same amount of muscle growth. Now in the new specific study, though, there was a curious finding because specifically for the Vastus Lateralis, the sweep of the quads, there was greater muscle growth,
• 02:30 - 03:00 significantly greater muscle growth in the slower eccentric training group. Now, how do we interpret this? What I've seen for most people looking at this study is that they say: “Ah! Haha! There is, in fact, greater muscle hypertrophy when we slow down our eccentrics because we get greater growth in the Vastus Lateralis.” However, there was no significantly greater growth in the total quadriceps as a whole. Moreover, none of the other four regions that were measured showed significantly greater muscle growth. So the greater growth in that one region could easily be a fluke. In statistical terms this is a Type I error.
• 03:00 - 03:30 Type I error can be thought of as a false positive. If you just test a whole bunch of different things, especially in a smaller, shorter study, then some of those things will end up being different between groups simply by chance. Like every time you do a study with measurements in every individual subject, maybe some of the subjects were just training harder, maybe some of them had better genetics, maybe some of them have different diets or something happened in the study, simply by chance there are individuals that get different results and even with randomization, sometimes more of those individuals
• 03:30 - 04:00 that had results in favor of one direction or in one group and therefore you get that one group having that result. Plus you simply have measurement error, where if you do a whole bunch of measurements and every measurement, especially with ultrasound, as was used in this study, which is sensitive to the operators proficiency, if you get some bias or error there, then you can get these random flukes. An analogy that I often see in clients is when they do a DEXA scan and they kind of obsess over the, you know, left arm versus right arm differences. Is my left arm growing versus the previous scan?
• 04:00 - 04:30 And those single site measurements are simply not very accurate. The total body fat percentage estimate from the body as a whole on your DEXA scans reasonably accurate. Like it's can still be off in a couple of percent. So even a DEXA scan is not a great way to measure your progress on an individual level. It's good in groups, but at the individual level not so much. But if you look at individual sites, the DEXA scan is really not accurate, not even at a group level. So the difference between right arm left arm is just such a small area that DEXA scan will not be that accurate. And also with ultrasound, if you do four different measurements,
• 04:30 - 05:00 then the chance of one of them being off is much greater than if you sum all of them together and you look at the total, the total is by far the most reliable. Basically, if you're saying that there was more muscle growth, you have to explain why. Well, there wasn't actually more total muscle growth, because if you look at the total amount of quadriceps muscle growth, it was nearly identical between the groups. An alternative way to interpret this is that there's regional hypertrophy. Some research indeed supports that the quadriceps has regional hypertrophy, where the eccentric face may activate the Vastus Lateralis more thereby accentuating the eccentric face might target more quad
• 05:00 - 05:30 sweep versus the teardrop, the VMO near the knee. I don't think this is a particularly strong interpretation, because research on regional differentiation in the quadriceps is very scarce. The quadriceps is a very simple muscle. It just extends the knee. That's it. At least the Vastae muscles. So if you look at something like the hamstrings or the deltoids, yes, we see significant functional differentiation. The different muscle heads even a different functions. So you can individually train certain heads and not the other heads. But with the quads that's not possible.
• 05:30 - 06:00 Most of the myths of, you know, squatting with your knees in narrow stance, targeting the VMO, get, you know, get more teardrop with special types of squats... Those have all been debunked. So there isn't very strong evidence for regional differentiation within the quadriceps muscles. Still, if we're not going by regional hypertrophy, and we're also not assuming that this is a fluke, the study would provide some evidence in favor of slower, eccentric speeds. However, if we're looking at regional measurements to support a case, then I can also pull up, for example, Pearson et al.,
• 06:00 - 06:30 which found actually greater growth with a faster eccentric tempo, which doesn't make a lot of sense to me, because theoretically you would expect that some degree of slowing down the eccentric, or at least controlling the eccentric, should be positive because you are stronger during the eccentric. If you're not controlling the eccentric, you're basically just dive bombing down, then there's essentially no eccentric muscle contraction, and you're just completely neglecting that phase of the movement, which is actually where we can get a lot of mechanical muscle tension. But that's all theoretical. In the end
• 06:30 - 07:00 we want empirical hard data. So in the Pearson study they looked at leg extensions performed with either a 1 seconds or a 3 seconds eccentric duration and interestingly, the 1 second eccentric duration group had greater gains in the distal quads. However, total quadricep size and strength gains were similar between groups. So again, I think it's most important to look at these total numbers. They are the most reliable and they are the most in line with the total body of research that we have. Most research does not support much effect of repetition tempo on muscle hypertrophy.
• 07:00 - 07:30 By the way, do you like my content? Then you'll love my online PT Certification course. Instead of spending 10 years sifting through misinformation and being confused by all the contradictory information on YouTube, in less than 1 year you'll learn absolutely everything you need to know to transform your physique and if you're a pro, the results of your plans. My research team and I have compiled quite literally all available information on muscle growth, fat loss, strength development and health sciences into a practical, take home messages to take your physique to the next level.
• 07:30 - 08:00 And we teach the methods that we ourselves actually use as coaches with our clients. Ranging from gen pop to professional bodybuilders. You'll also get a PT toolkit with calculators, case studies, how to guides, an exercise library, and hefty discounts to our partners products and services. Of course, you shouldn't take my word for it, check out the reviews of our former students in the link below. To my knowledge, we have the highest student satisfaction scores in the market. Okay, back to the video. For strength development, this study had an even crazier finding because the 4 seconds
• 08:00 - 08:30 eccentric group in this study actually gained significantly more strength. 1RM strength gains were greater in the squat group doing 4 second eccentrics than the group doing the 1 second eccentrics. And this directly contradicts the earlier review and a study by Shibata et al. from 2021. They looked at squats with either a 2 or a 4 second eccentric tempo, and they found that strength gains were greater with the 2 second eccentric tempo. This makes sense because strength gains are velocity specific, and there is a thing called the stretch reflex, whereby if you lower a weight
• 08:30 - 09:00 a bit more rapidly, still under control, but a bit more rapidly, you get what's called a stretch reflex. And this is not just elastic tension like you bounce on your tendons. There's actually also a signal being sent from the brain to the muscle when it is lengthening, especially when it is lengthening more rapidly to activate the muscle. So you get higher levels of muscle activity, active muscle tension is a little bit higher when you do a faster eccentric repetition. So mechanistically, it makes sense that a faster eccentric repetition would be better for strength development, especially if you want to be stronger
• 09:00 - 09:30 with that repetition. If you have to do a very slow 1RM, then maybe it's better to actually train at that repetition speed. It's interesting that these studies had essentially polar opposite conclusions because they were both on squats, they were both on essentially endurance trained Individuals, because in the Shibata study they were soccer players, and they both used a relatively similar training intensity. However, the Shibata study, the older one, they had an intensity of 75% of 1RM and in the current new study they used an intensity of 60 to 70% of 1RM. And if you look at the number of repetitions that they did here
• 09:30 - 10:00 you can see that the repetitions were very high and I think this might be a reason that the faster tempo group in this study was doing essentially their reps at 15 rep max, which is very high for squats, so maybe that's the reason that that was inferior for strength development. You actually run into issues with just cardio, you know, getting out of breath, not being as explosive. Squats don't lend themselves particularly well to doing sets of 15 for most individuals. So how do we interpret this new study in light of all previous research? I think a lot of people, and I see this all the time now on social media, people
• 10:00 - 10:30 hyperfocus on these individual findings of individual studies, and they are like: “Oh, one study says this, one study says this, and like every new study, says something completely different.” And they're just getting completely lost in these minor details. It's normal and expected that every time you do a study the findings are going to differ a little bit. So if you take a little bit of a bigger picture look it's actually very clear that most research does not find significant differences on strength development or muscle growth of the eccentric speed. If you look at some of the individual studies and also in the current new studies
• 10:30 - 11:00 I do think that it is very important that you control the eccentric phase, even if simply, theoretically, mechanistically, we know that the eccentric muscle phase is where you can generate very high mechanical tension and we know that mechanical tension is the primary driver of muscle growth. So it makes perfect sense that we have to have a significant eccentric muscle contraction during every repetition. As long as you are controlling the descent, then you're probably fine and you don't have to actively slow down your repetitions. As for the concentric speeds, the new study didn't touch on that, but the short version is that for strength
• 11:00 - 11:30 development - research it's quite clear that you want an explosive concentric and for muscle growth it doesn't matter so much. You probably want to focus on a repetition tempo that allows you to perform as many repetitions as you can. But again, most research is aligned that repetition tempo just doesn't have much effect on your gains, so you can use whatever tempo you personally prefer. In that sense, I do recommend that people don't count the repetitions because a 4 second eccentric duration during your squat is a hell of a long time. Try actually doing it with a metronome and you'll see nobody does a 4 second
• 11:30 - 12:00 eccentric contraction outside of these studies where there's literally some guy timing you. So I recommend just controlling the descent but not worrying about counting or any specific tempo and then lifting the weight either explosively if your goal is strength or just lifting it in a way that allows you to do as many reps as you can for muscle hypertrophy. Alright! I hope that helps you with your gains. If you like this type of evidence based contact I'd be honored if you like and subscribe.