Eccentric Exercise

You've probably heard the terms 'eccentric' and 'eccentrically' being discussed within strength and conditioning, endurance, or even rehabilitation discourse. But what exactly are eccentric exercises, and why are they beneficial?

Eccentric exercises are steady contractions that lengthen a specific muscle. Eccentric exercises are performed slowly with control, such as slowly sitting down on a chair, adding to the muscle's time under tension.

Eccentric vs. Concentric Exercise

What Is The Difference?

The concentric phase of a movement is when the muscle’s tension increases and the fibers contract, meaning they shorten.

For example, when performing a bicep curl, curling the dumbbell is the concentric or shortening phase for the biceps, and the lowering phase is the eccentric phase.

Examples of concentric exercises include
  • The first half of a deadlift, or lifting an object off the ground
  • Pressing to the top in a push-up
  • Standing up during a squat
  • Hamstring curl
  • The upward motion of a sit-up

On the other hand, muscles lengthen under tension with eccentric exercises, creating an adaptation that improves performance.

Why Use Eccentric Exercise?

Low Metabolic Cost

A study on nine healthy subjects, ages 18-34, found that eccentric exercises increased muscle strength, via eccentric work, with little demand for oxygen. They observed significant gains in isometric leg strength for the eccentrically trained subjects only.

The oxygen consumption required to do the eccentric work was equal to or less than that of the concentric work. The findings showed that you can make significant isometric strength gains with a minimal increase in metabolic demand for oxygen by progressively increasing the eccentric work rate.

Increase Flexibility By Increasing Muscle Length

Emerging studies have found that you can shift the optimum length-tension relationship in muscle to longer muscle lengths after certain types of eccentric exercise.

These are particularly interesting as greater structural stability at longer muscle lengths may positively impact injury prevention and athletic performance. Because of this, the effects of eccentric exercise on muscle injury prevention and athletic performance are of high interest to researchers.

Produce more force

A study on trained rugby players looked at the effects of slow and fast tempo resistance training incorporating accentuated eccentric loading (AEL) compared with traditional resistance training (TRT).

They found that slow AEL improved back squat 1RM and sprint speed versus slow TRT. Their findings were that the short-term incorporation of slow AEL was superior to TRT in enhancing strength and maximum velocity sprinting speed in rugby players undertaking a concurrent preparatory program.

Maintain Type IIX Muscle Fibers

A systematic review looked at the effects of eccentric training vs. concentric only resistance training. They found that eccentric training elicited more significant improvements in muscle strength, superior enhancements in power, and stretch-shortening cycle (SSC) function.

Furthermore, a preferential increase in the size of type II muscle fibers and the potential to exert a unique effect upon fiber type transitions was also reported.

Jump Higher and Sprint Faster

Eccentric training is a potent stimulus for enhancements in mechanical muscle function muscle-tendon unit morphological and architectural adaptations.

The same study on the effects of eccentric training compared to concentric-only resistance training found that eccentric training led to qualitative and quantitative changes in tendon tissue related to the magnitude of strain imposed.

Eccentric Exercise Examples

Here’s a series of eccentric exercises which you can achieve with Exerfly's equipment.

Delayed Braking Action

  • Eccentric overload is achieved most commonly through a delayed braking action.
  • Resist maximally near the end of the movement.
  • For example, in a squat, ride the flywheel down and try to stop the flywheel with maximum force at the very end of the movement.
  • This eccentrically overloads the end range as you’re trying to stop movement in a short period.
  • The peak eccentric forces generated are massive.
  • Video example is James performing a flywheel delayed eccentric braking squat.

Impulse Overload

  • Impulse overload involves positioning yourself in the eccentric phase, so the load hits you, and you need to stop it.
  • For example, position yourself in a half squat and let the weight hit you.
  • You need to be able to quickly brake eccentrically.
  • Video example is James performing a flywheel impulse overload squat.

2 Up, 1 Down

  • Two up, one down is a strategy often used with machine-based training.
  • For example, in a lying leg curl, you can use heavier loads by using two legs to lift the weight.
  • Resisting on the way down with one leg eccentrically overloads the working muscles.
  • Video example James performing a 2 up, 1 down flywheel squat


  • Priming exercise takes advantage of the post-activation potentiation phenomenon.
  • Considering there is little difference between using the flywheel or barbell for priming exercise, try flywheel training before activities or competitions where barbells and weights are not available.
  • According to James, 5-6 maximal reps on the flywheel are far less fatiguing than performing a heavy barbell exercise.
  • Video example is James performing an isometric flywheel deadlift.

For a detailed video breakdown on doing these exercises, visit Exerfly's video catalogue of easy-to-follow tutorials here.

Exerfly Products



form 9698


form 3507


form 2184

Motorized Technology


Exerfly Products

Flywheel training offers many advantages over traditional training, with variable resistance being a significant factor. There is no limit to the kinetic energy you can generate with Exerfly equipment. This means that you can always use a higher force and accelerate more. If you plateau, you can use the motorized technology to boost the eccentric phase.

Therefore, our equipment is suitable for all types of training- heavy strength training to rehabilitation- and users of different backgrounds and abilities. The more inertia added to Exerfly equipment, the more force can be produced by the user, which you can record via the app.

Chris Chase Portrait
Chris Chase
Director of Performance - Memphis Grizzlies

Both the exerfly portable and platform products will continue to be beneficial for our basketball players. The unique resistance profile can facilitate higher impulse-oriented loading at troublesome joint angles, such as deeper ranges of flexion during squatting exercises.
Traveling with the Exerfly Portable has added immense value to our training on the road. The type of resistance provided by the flywheel is just something that is hard to mimic without the equipment itself. The Portable is extremely easy to set up and break down, and has stood up against the rigors of NBA travel.
The versatility of the Exerfly Platform is unmatched by any other piece of flywheel equipment on the market. Firstly, being able to use 1 or 2 straps is a huge advantage. Unlike other equipment with 1 strap , the Platform can be better set up for things like deadlifts with 2 separate handles or a shoulders elevated hip bridge with a straight bar. This has allowed us to utilize the flywheel stress with most of our exercises.
The Platform motor feature also has huge potential to enhance our training in our foundational exercises like squatting and hinging. Basketball players are subjected to immense forces as they move into and out of positions of ankle, knee, and hip flexion. The Platform motor can increase the speed of the spinning wheel during the eccentric portion of the exercise, facilitating higher force outputs that would be hard to mimic using any other method.
I believe the Exerfly products provide a type of stressor at an intensity that will allow us to make serious improvements in our KPIs.
We are lucky that the Exerfly company has been responsive, open minded, and eager to innovate using the feedback of coaches in the field. They are already ahead of most other companies in this particular space, and we are excited for the continued evolution!

Angus Ross Portrait
Angus Ross
World-Renowned Strength & Conditioning Coach and Researcher, 3x Bobsleigh Olympian.

“The sports that I work with predominantly are very measured, so physical performance is a prerequisite. Trying to develop that physicality has become somewhat of an obsession of mine, and I like to find ways of doing things better – which is why I use Exerfly.”
“The athletes I work with are speed and power athletes, so physical performance is a prerequisite. We’ve been using Exerfly for several years now, and the ability to train these high power qualities in different planes, rotationally, and in different aspects has been extremely advantageous. I’m using it because it works.”
“The ability to take Exerfly and travel with it has been something that I’ve never seen before, and there’s a lot of elite athletes around the globe now using Exerfly. And that’s a testimony to the company, that Exerfly has been flexible and has continued to develop.”
“Most of the movements we do in sports are not strength orientated, they’re power orientated. And most of that is high-velocity power. For somebody to jump high or run fast, it’s not a slow grinding strength like you might see in powerlifting – it’s elastic power and high-speed muscle power, and you can train both of these with Exerfly.”

Jerome Simian Portrait
Jerome Simian
Owner of Synaptic Athletics sarl. Coached athletes who medalled internationally in seven different disciplines. Coached Kevin Mayer to a world record in decathlon. 20-year career athletes have participated in eight Olympics and have made countless national team selections. He also trained successful athletes for sports as diverse as pro rugby, figure skating, skeleton judo, golf, soccer and bobsled to name a few.

When it comes to strength training equipment for my athletes, I am of the minimalistic camp. I really like the adjustable rack mounted flywheel from exerfly. First of all for its versatility as the adjustable height opens up many possibilities for different exercises as well as stressing different portions of the same exercise. It is also important that the flywheel comes with measuring capabilities and a simple app that tells you what amount of work is done which is not always the case with inertial equipment. I am grateful to exerfly for the quality of their product and the quick customer service they provide despite being exactly on the other side of the world from me.

Victoria Azarenka Portrait
Victoria Azarenka
Two-time grand slam champion, Olympic Gold Medalist and the 2012 Grand Slam winner

I like the ability to introduce a different way of training regimen into my schedule and routine. It gives my body a different way of adapting to load and intensity. Exerfly has increased power and endurance during strength sessions and explosiveness. Exerfly equipment has been a great addition to my strength component as well as strength endurance. Full body workouts are very challenging with limitless moderation of effort. I have enjoyed a lot for the communication and introduction to Exerfly and the expertise to get the best out of the equipment.

Vern Gambetta Portrait
Vern Gambetta
Vern is currently is the Director of Gambetta Sports Training Systems. He has been the a conditioning coach for several teams in Major League Soccer as well as the conditioning consultant to the US Men’s World Cup Soccer team. Vern is the former Director of Conditioning for the Chicago White Sox and Director of Athletic Development for the New York Mets. Vern is recognized internationally as an expert in training.

Exerfly is my equipment of choice in flywheel training technology. The equipment is versatile and easy to use. I have found the rack mounted unity system especially effective in my work with throwers, volleyball players and swimmers. A very versatile tool.

Exerfly Equipment

PNG picture of exerfly flywheel training platform


The Exerfly Platform is a stable, multi-use flywheel training platform built for everything from heavy duty workouts to rehabilitation.

Learn more
PNG picture of exerfly portable


The Exerfly Platform is a stable, multi-use flywheel training platform built for everything from heavy duty workouts to rehabilitation.

Learn more
PNG picture of exerfly rack-fly


The Exerfly Platform is a stable, multi-use flywheel training platform built for everything from heavy duty workouts to rehabilitation.

Learn more
PNG picture of exerfly ultimate


The Exerfly Platform is a stable, multi-use flywheel training platform built for everything from heavy duty workouts to rehabilitation.

Learn more
PNG picture of exerfly accessories


The Exerfly Platform is a stable, multi-use flywheel training platform built for everything from heavy duty workouts to rehabilitation.

Don’t know which equipment to choose?


Trusted by the world’s best athletes, coaches, and teams.

Train at a higher level

  • Icon of 30-day money-back guarantee

    30 days

    Money-back guarantee

  • Icon of 2-year Warranty

    2 years


  • Icon of Free Shipping


    Shipping and taxes

Free Consultation