What is Continuous Tension Training?
One of the ways to increase the difficulty of an exercise without increasing the weight is to maintain continuous tension in the muscle. This means that at no time during the movement will you let the muscle relax or “breathe.” In other words, you have to maintain the tension on the muscle throughout the entire range of motion of an exercise, for the complete duration of a set. This is the short story behind the principle of continuous tension in strength training.
Muscles respond favorably when they’re placed under continuous tension with no resting phases during the rep. Therefore, lifting weights with continuous tension can provide a potent stimulus for muscular hypertrophy, even when you use relatively light loads.
Example of Continuous Tension Training
The beauty of the constant tension method is that it can be applied to virtually any exercise. For example, while doing push-ups, when you hover with your arms extended, your skeleton is supporting the weight of your body and not your muscles. In this position, your muscles can recover somewhat.
The principle of continuous tension means eliminating the phase where the arms (or the legs) are extended. The whole time you are doing push-ups, you keep your arms slightly bent. An intense burn will quickly develop in the muscle because of the intracellular asphyxiation you are creating. In effect, by constantly keeping the muscles under tension, you are blocking the circulation of blood. Without oxygen, the muscles produce a lot of waste (lactic acid) when they synthesize their energy.
For a chest exercise like the dumbbell or barbell press this would mean not fully locking out at the top of the lift. At the top of an incline press, for instance, when the arms are fully extended, the skeleton supports the load, relieving the tension on the muscles for a brief moment before the weight is lowered. During this pause, tension is taken off the muscle, the muscle gets a brief rest, and therefore, intensity is compromised.
The same principle applies to the shoulders, back, biceps, or triceps. You never straighten your arms during the exercise. For the quads, you never completely straighten the portion of your legs above the knees. Ideally, you should use a mixture: continuous tension and rest break. You begin the movement with continuous tension. When the pain becomes too much to bear, you take a break (arms or legs straight) so that some of the lactic acid can leave the muscles. The exercise can then continue for one or two additional repetitions.
How to Apply the Principle to Various Exercises?
Here is how to apply the principle to various exercises:
- During back, biceps, and hamstring movements, do not straighten your arms or your legs completely in the stretched position.
- During chest, shoulders, triceps, and quadriceps exercises, do not straighten your arms or your legs completely in the contracted position.
Note: Except for the deadlift, there is no loss of tension at the top of the contraction phase in back and hamstring movements. This differs from most of the basic chest and quadriceps exercises, in which you often lose tension at the top of the contracting phase.
When To Use Continuous Tension?
You can apply this principle to virtually any exercise. However, you’ll find it’s most useful when applied to free-weight movements.
Because of the nature of machine-based exercises, there’s no need to augment them to achieve constant tension. To understand free-weight vs. machine biomechanics, let’s use a biceps curl for example.
During any style of biceps curl, the point at which your biceps are maximally loaded is the point in the range of motion in which your forearm is at a 90-degree angle with the load vector. If you’re using free weights, gravity is your load vector. So the point of maximal loading would be when your elbow reaches 90 degrees of flexion or when your forearm is parallel to the floor. The farther your elbow flexes (or extends) beyond that 90-degree angle, the less stress you’ll place on your biceps. In other words, during a free-weight biceps curl, as the dumbbell approaches either your shoulder in the top of the motion or your thighs in the bottom, your biceps are receiving significantly less stimulation.
Machines for the most part, unlike free weights and cables, are neither gravity dependant nor load-vector dependant. Because of their cam-based design, they provide constant tension to the working muscle throughout the entire range of motion. So when you perform biceps curls on a machine, you’re working just as hard at the bottom position (elbows extended) as during the mid-range and at the top position (elbows fully flexed).
What can we conclude from this? If used properly, machines can be a powerful weapon in your muscle building arsenal. And despite the importance of compound free-weight movements for increasing size and strength, anyone whose main goal is muscle hypertrophy should absolutely include machines in his program.
Top 3 Benefits of Using The Principle of Continuous Tension in Strength Training
The principle of continuous tension is an advanced bodybuilding technique that can help you to:
- Increase the intensity of your workouts and therefore speed up your results;
- increasing muscle size and hardness, particularly in isolation exercises;
- Save your joints from excessive wear and tear;
- Keep you from possibly injuring yourself;
Continuous Tension vs. Time Under Tension (TUT)
Classic tension training has two main components: time under tension and constant tension. Time under tension, or TUT, deals with the total time a muscle is worked, meaning total number of seconds in a work set. Constant tension means keeping tension on the muscle for the entire work set, meaning you won’t lock out fully during a set.
For example, you might see “3-1-2” for a biceps curl. The first number is the first part of the movement (depending on the movement it could be a contraction or an extension), the second number is the pause, while the third number is the return to the start position:
- Count to 3 as the dumbbells come closer to your chest.
- Pause for 1 count with the biceps fully contracted.
- Count to 2 as you return the weight back to the start position.
Maintaining continuous tension in the muscle throughout the repetitions is a good way to increase difficulty without increasing weight. To maintain continuous tension you must avoid the completely extended portion of the exercise. You will easily achieve this by keeping your arms or legs slightly bent (contracted) at all times. The principle of continuous tension requires great exercise form and control, so it is not for beginners.