Concentric Exercise – What Is It?
The term “concentric” refers to the action of contracting muscles during movement. When it comes to strength training, there are two types of muscle contractions: concentric and eccentric. The difference between them is how fast they occur. For example, when you pull your arm back, the muscles lengthen and shorten at different rates depending on their length (eccentric) or speed (concentric).
When you perform a lift with your arms straight out in front of you, the fastest part of the movement occurs during the concentric portion. During this time, your body is moving forward. Your legs move first and then your torso moves laterally until reaching full extension.
At this point, your arms are still straight out in front of you so they aren’t involved in any type of eccentric motion.
In contrast, when you perform a lift with your arms bent at 90 degrees, the slowest part of the movement occurs during the eccentric portion. During this time, your body is moving backward and your legs move first before your torso moves laterally. At this point, your arms are still bent at 90 degrees so they’re not involved in any type of concentric motion.
Eccentric Training – What Is It?
The term “eccentric” refers to the action of the muscles when they’re lengthening under load. Muscles lengthen due to gravity or the force applied by the opposing limb or weight. The lowering portion of a bicep curl, for example, is the eccentric motion because the bicep is actually lengthening. The lowering portion of a squat is an eccentric motion because the muscles are actually lengthening due to the force of gravity.
During an eccentric contraction, muscle tissue can be torn and damaged but this isn’t a bad thing. In fact, it’s beneficial because it ultimately makes your muscles stronger. When you tear a muscle during an eccentric motion, it adapts by becoming thicker and stronger in order to prevent itself from being torn again.
This is the reason why strength training increases your muscle mass.
In short, eccentric muscle contractions are:
Beneficial for building strength
Involved in all types of exercise (even concentric contractions use them to a small degree)
Useful for treating and preventing injury
While everyone focuses on the benefits of concentric contractions, eccentric contractions are far more beneficial for overall health and fitness. Despite this, eccentric training is underused by most trainees and trainers.
When Should You Use Concentric or Eccentric Training?
Concentric training involves shortening a muscle under load. For example, doing a leg extension would require you to push your leg forward until your foot touches the machine. This would be a concentric motion for your quadriceps. In general, most exercises are concentric because you’re lifting the weight.
Eccentric training involves lengthening a muscle under load. For example, doing a leg curl would require you to pull your leg back to the starting position. This would be an eccentric motion for your quadriceps.
Some exercises use both of these motions.
Although most exercises involve concentric motions, eccentric training is beneficial for all of them because it helps to reduce the risk of injury and helps build strength. For example, runners are more prone to patellar tendonitis, a condition causing pain and swelling of the kneecap and tendon. This is due to eccentric training being neglected by most runners.
By doing some eccentric training for your legs, you can strengthen the quadriceps and the kneecap tendon itself. This will allow you to run longer distances without getting injured as easily.
Even though eccentric training is useful for runners, most people don’t do enough of it. If you’re not involved in a sport that requires eccentric strength, such as sprinting or jumping, then you should do some extra eccentric training 2-3 times a week for the specific muscle group. If you play sports, you can get away with doing it just once or twice a week.
For each exercise, choose a weight where you can easily perform 20 reps. If you can easily do more than 20 reps, then the weight is too light. If you can’t do at least 12 reps, then the weight is too heavy.
If you chose correctly, the last couple of reps in each set should be very hard. This will ensure that you’re targeting your fast-twitch muscle fibers which are prone to growth and strength.
Ideally, you should pick a free weight exercise for one of your weekly sessions and machines for the other. This will allow for balanced development. If you only have access to machines, don’t worry.
You can still do all of the exercises. It’s just best to have free weights as well since they provide more overall benefits.
Rest 60-90 seconds between sets.
Barbell Back Squat
How To: Stand with your feet slightly wider than shoulder width. Grab a barbell with an overhand grip, letting it rest on your front thighs. This is the starting position.
Keeping your back straight, bend your knees and lower your hips back as far as you can. Then, push up through your heels to return to the starting position.
How To: Grab a barbell and let it rest on your shoulders. Step forward with one leg and lower your body until that thigh is parallel to the ground. The other leg should be straightened behind you.
From this position, push through the front foot to return to the starting position and then repeat with the opposite leg.
Barbell Step Up
How To: Place one foot on a bench or box (whatever is available) that is around mid-calf height. With the other foot, push through the floor and then up onto the box. Then, step back down with that foot and repeat with the opposite leg.
Dumbbell Romanian Deadlift
How To: Stand up straight while holding two dumbbells at your sides. Keep your back straight and head up, and bend at the knees as you hinge forward at the waist. Let the dumbbells hang, palms turned outwards, just outside your legs.
Pause at the bottom of the movement, and then squeeze your glutes and hamstrings to stand back up.
How To: Set a thigh extension machine to a medium resistance setting. Sit on the machine with both legs, and place your feet flat on the foot plate. Keeping your knees together, push the thighs forward until your legs are fully extended.
Then, flex your quadriceps to bring the legs back to the starting position.
How To: Set a leg press machine to a medium resistance setting. Place your feet flat on the foot plate and let your knees bend about 90 degrees so that both legs are bent at the hips at about a 45-degree angle. From this position push the sled until your legs are straight.
How To: Set a seated calf raise machine to a medium resistance setting. Sit down on the machine with your legs in front of you, let your knees bend about 90 degrees, and place your feet on the foot plate. Keeping your back and neck straight, push up on the handles to raise your heels as high as you can.
Lower the heels down slowly, and repeat.
The Program: Weeks 1-4
The program lasts four weeks. After that, you get a week off from this program (though you can still do the workout routines if you want). You can then repeat the program over again starting with week one.
Mark the date that you started at the top of the worksheet. This will help you keep track of when your week breaks are and when your progress pictures should be taken.
During the first two weeks of this program, you’ll be training three times a week. During the last two weeks, you’ll train four times a week to get ready for Week 5. Each workout routine has a “Workout” section and a “Weight” section.
The “Workout” section tells you which exercises to do and the order in which to do those exercises. The “Weight” section tells you how much weight to use for each exercise. It is VERY important that you select a weight that is light enough for you to complete the required number of repetitions listed next to the exercise (the number set inside the (“”) sign).
For example, if you start this program and your leg press is 300 pounds, then you’ll do your leg presses with 300 pounds. However, if your leg press is 200 pounds, then you will need to do them with 200 pounds. If your leg press is 300 pounds but you can only do them for 8 repetitions (8 being the number listed next to the exercise), then you’ll need to decrease the weight until you can reach 12 or more repetitions.
Only once you reach 12 or more repetitions at the current weight should you even consider increasing the weight. And, when you do increase the weight, increase the weight by only a small amount.
If you’re using proper form and you’re simply unable to lift a weight through the full range of motion, don’t try to lift the weight. Increase the weight and try again or decrease the weight and continue to try to lift it until you succeed.
Rest in between each set.
The guidelines state 2-5 minutes but this depends on how much weight you’re lifting and how many repetitions you’re trying to achieve. For example, if you’re lifting a weight that you can only do 6 reps with, you’ll probably need to rest longer than if you were lifting a weight that you can do 18 reps with. While resting in between sets, do some light cardio or jump around a bit.
Also, try to increase the amount of weight that you lift over the course of this program. For most people, once they can do 12 repetitions with a weight, they should continue to use that weight until they can do 12 reps with it no longer; then increase the weight by a small increment. Some people may be able to increase the weight more than others.
Sources & references used in this article:
The importance of muscular strength: training considerations by TJ Suchomel, S Nimphius, CR Bellon, MH Stone – Sports medicine, 2018 – Springer
Eccentric versus concentric resistance training to enhance neuromuscular activation and walking speed following stroke by DJ Clark, C Patten – Neurorehabilitation and neural repair, 2013 – journals.sagepub.com
… training compared to unsupervised home-based exercise after fast-track total hip replacement applied to patients with preoperative functional limitations. A … by LR Mikkelsen, I Mechlenburg, K Søballe… – Osteoarthritis and …, 2014 – Elsevier
Alterations in speed of squat movement and the use of accommodated resistance among college athletes training for power by MR Rhea, JG Kenn, BM Dermody – The Journal of Strength & …, 2009 – journals.lww.com