Let's see the what is the difference between isotonic vs. isometric exercise and which one is better for you.
Exercise, to most people, normally involves following a workout program, use of exercise equipment, hiring a trainer and trusting them to guide you to the results you want-a toned body, slimmer waist, and stronger muscles, just to name a few. But how do you know that these exercises are effective, and how do they change your body?
This article will give you a beginner's guide to understanding the various categories of muscle contraction: isotonic (concentric and eccentric) and isometric-and how they affect your fitness regimen. Understanding these muscle movements can help you choose the right types of workout to target problem areas, giving you a better and more effective workout.
Understanding Muscle Contractions
To better understand the concepts and allow you to plan your fitness strategy, it's important to learn about muscle kinesiology or what happens when your muscles move. There are two basic categories of muscle contractions: isotonic and isometric.
Isotonic Contractions
Isotonic contractions involve the shortening (concentric) or lengthening (eccentric) of muscles which can be produced with movement. In isotonic contractions, the muscles maintain equal tone, while the length changes.
Concentric Contractions
During concentric muscle contraction, the activated muscles shorten when lifting a load that is less than the maximum force the muscles can generate. This movement goes against gravity, therefore improving the muscle's ability to pull and lift. A great example of concentric contractions is when you're raising a dumbbell in a bicep curl.
Eccentric Contractions
In eccentric muscle contraction, however, the muscles lengthen while generating force. It utilizes the same set of muscles, but eccentric contractions happen when you're returning from a concentric movement to a resting position, such as when you're extending your arm (after lifting) during a bicep curl. In this case, the weight is greater than the force your arm can produce.
The muscle lengthens, making the connection points move farther apart. However, the muscle is still contracting and exerting force on the weight. This acts as the body's braking mechanism, which slows the lowering movement to prevent the weight from pulling down too fast from gravity.
Isometric Contractions
Meanwhile, in Isometric contractions, the muscles generate force while maintaining equal measure or length. To put it simply, your muscles contract even while maintaining a still position, such as when you hold the dumbbell in place at a 90-degree angle during a bicep curl.
Why do I need to know the types of muscle contractions?
When designing your fitness regimen, it's a good strategy to include both isotonic and isometric exercises. While most fitness programs include both, the time you spend on each one will greatly affect your results.
For instance, you may find it easy to lift a 10-pound dumbbell, but easier to hold and lower a 15- or 20-pound dumbbell during a biceps curl. And because your muscles generate more force during the eccentric phase, slowing down or extending this part of the exercise will help you build greater strength.
You can also use eccentric contractions to help you progress to more difficult exercises. For example, if you're not yet strong enough to lift yourself all the way up (concentric) to do a complete pull-up, then you can use a box or chair to help you, then slowly lower yourself down (eccentric). In effect, you're still working the same muscles and reaping the same benefits as you would with a complete pull-up.
Isotonic vs Isometric Exercises - What are the benefits?
Both isotonic and isometric exercises are excellent for strength training and muscle building. Performing these exercises will also help you prevent heart problems and improve your overall health and fitness. And while they share these benefits, they each have unique advantages, too, which will help you determine which one is right for your fitness goals.
Requires weights, dumbbells, and other equipment
Little or no special equipment is necessary
Repetitive movements - the standard recommendation is three sets of 10 to 15 repetitions
Requires less time to perform - 15 to 30 seconds for each exercise will suffice
Increases muscle strength, mass, and size
Maintains muscle tone and shape but builds muscle size when done with weights
Increases fat-free mass and reduces body fat
Helps in weight loss and weight management
Improves bone density and reduces the risk of osteoporosis
Improves joint flexibility and strength
Trains your body for movements and activities for daily living
Addresses weaknesses and imbalances so you can progress to more advanced training programs
More blood is pumped, thereby boosting cardiovascular health
Improves cholesterol levels and lowers blood pressure
Maintains metabolism rates as you age
Maintains muscle strength during injury recovery and rehabilitation
Requires full range of motion
Can be performed seated, making it advantageous for the elderly and disabled
Examples of Isotonic and Isometric Exercises
Some exercises can be both isotonic and isometric
For isometrics exercises, you simply need to hold the pose for as long as you can. And to turn it isotonic, you can perform as many repetitions as your workout regimen requires. Here are some exercises you can use and the specific muscle groups they target.
Place yourself on prone position with your hands on the floor, parallel to your shoulders. Keep your feet on your toes to lift your body.
Position yourself on your hands or forearms, keeping them parallel to your shoulders. Lift yourself on your toes and keep your back straight. Tighten your core and glutes to keep the length of your body straight.
Start by standing upright. Slowly lower yourself by sticking your glutes out behind and bending your knees. Keep your knees behind your toes.
Glute Bridge
Lie on your back and bend your knees with your toes and heels flat on the ground. Lay your palms on the floor, parallel to your shoulders. Lift your glutes and tighten your core, keeping your abdomen aligned with your knees.
Lie prone on the floor with your hands extended above your head. Place your palms on the floor and keep your knees together. Raise your hands and legs high off the floor without bending your elbows and knees.
Bottom Line
Given the unique benefits of isotonic and isometric exercises, you can now better understand how your muscles move for the types of workout routines you choose. In addition, you can also determine whether you're doing a particular exercise correctly. Are the right muscles being activated? Do you feel them shortening, lengthening, and contracting? Are you maintaining the right tension?