- Sebastien Lagree is a celebrity trainer whose fans include Meghan Markle, Jennifer Aniston, Sofia Vergara, Karlie Kloss, Michelle Obama, and Calvin Harris.
- His training method is all about focusing on “time under tension.”
- This means performing movements slowly – ie. taking 8-10 seconds to lift a weight and the same amount of time to lower it – to stimulate the slow-twitch muscle fibres.
- Lagree says this is the way to sculpt a lean physique.
- However according to other fitness experts, the method may not be right for everyone depending on your goals.
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In today’s fast-paced world, using our limited time effectively is of the utmost importance.
This has led to the rise of short, sharp, high intensity workouts, many of which promise to work your body as efficiently as possible in as little as 20 minutes by moving fast and limiting rest time.
But according to one personal trainer, rushing through a workout isn’t the way to go.
Celebrity trainer Sebastien Lagree has worked with a seemingly never-ending list of celebrities – fans of his training method include Khloe and Kim Kardashian, Meghan Markle, Jennifer Aniston, Ivanka Trump, Ashley Graham, Rihanna, Alessandra Ambrosio, Karlie Kloss, Courteney Cox, Nicole Kidman, Sofia Vergara, Vanessa Hudgens, Scott Eastwood, Britney Spears, Lea Michele, Eva Longoria, Elizabeth Hurley, Lady Gaga, Michelle Obama, and Calvin Harris.
And Lagree, an ex-body-builder turned fitness engineer and creator of the Lagree Fitness Method and Megaformer machine, is a staunch advocate of slowing down workouts and focusing on "time under tension" (TUT).
Read more: You're probably squatting wrong, according to Ellie Goulding's personal trainer
Essentially, this means performing each move incredibly slowly so as to increase the length of time the muscles are working.
Lagree believes this is the way to see results, not lifting heavier weights.
"The key to building muscle strength and endurance, while burning fat, lies in intensifying your workout by having more control and less momentum behind each lift," he said.
How to increase time under tension
The TUT approach can be applied to most movements you might perform in the gym, from a simple bicep curl to a bench press.
Lagree suggests taking 8 to 10 seconds to lift a weight, and another 8 to 10 to return to your starting point. And if you're holding a position, do so for a minute.
"You need to perform or hold the movement/position you're in for a minimum of 60 seconds to achieve or improve muscular endurance," Lagree told INSIDER.
"Muscular endurance is the strengthening, tightening, toning, and sculpting of the muscles."
He believes explosive movements are to be avoided and stresses that you shouldn't try to lift too heavy, because you won't be able to.
"By moving slowly for a long time (ie: anywhere from 60 - 120 seconds), you're preventing your body from cheating, so you're getting a much deeper muscle fatigue because your muscles are doing all the work," Lagree explained.
"Using momentum to power movements is what leads to potential injury of connective tissues because you're combining force with speed. If you lift with a lot of acceleration, you create momentum."
Why might TUT be better?
Lagree believes one of the main benefits of the TUT method is that it teaches you to lift with control.
"When you move slowly, it forces your body to create more nerve-endings around the muscle, which is good for your mind-body connection and concentration on the movements," he explained.
"You will get a better response from working out because you will activate more muscle fibers. When you're just using explosive movements, you're only activating mostly the fast-twitch muscle fibers, which are responsible for building bulk."
According to Lagree, explosive movements performed with momentum are more likely to result in injury too: "The connective tissues that attach your muscles to bones, that's at risk, because really you're creating artificial resistance with speed; this can lead to micro-tears in ligaments and tendons, and worse," he said.
It's safer to use lighter weights and focus on the length of time that the muscle is being contracted, he said.
However, not everyone is convinced by these claims - Rick Howard, M.Ed, C.S.C.S., for example, told Men's Health that TUT actually isn't less likely to result in injury than more explosive movements, so the jury is out.
Is TUT right for everyone?
If it's true that explosive movements result in muscle bulk, should you skip TUT if you're actively trying to build muscle?
Not necessarily.
While TUT might not be the main component of your workouts, Lagree says you should still weave it in alongside explosive movements to make sure you're building the foundation of the muscle's structure by strengthening those underlying slow twitch muscle fibers.
You can still employ progressive overload with the TUT method too.
Building muscle size (hypertrophy) is different from building strength though, and as such the two goals require different training methods, as human movement and elite performance specialist Luke Worthington, a Certified Strength and Conditioning Specialist, Integrative Corrective Exercise Specialist, and Master of Science in Biomechanics, explained to INSIDER.
"Training to increase strength and power requires lifting the weight with intent and explosively," said Worthington, who believes that focusing on TUT alone may not be enough to reach your goals.
"Caveat this by saying that hypertrophy training also requires adequate force production to produce metabolic damage to the muscle fibres in order to stimulate growth.
"Doing multiple slow deliberate reps without adequate resistance will create muscle soreness, but not an increase in its size or strength."
Worthington advises tailoring your training style to your goal:
- To increase muscle size (hypertrophy), do 12-15 reps with a moderate to heavy weight.
- To build muscle strength, do 4-6 reps with a heavy weight.
- To improve muscle power, do 4-6 reps with a medium to low weight, but move fast.
"Performing 15 or more reps with low weights will only really create soreness," Worthington said. "Which can be helpful in a rehab program to help someone 'find' a muscle in the days following a workout, but not useful for changing its appearance or performance."
TUT certainly has benefits, but whether it's going to have a dramatic effect on your fitness - and physique - depends on your goals.