Time Under Tension - Possibly more Important than Sets & Reps

Time Under Tension

How to Add New Dimensions to Your Physique

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The process of building muscle is fascinating It's both extremely simple, yet infinitely complex. Saying it takes a heck of a lot of work is no surprise. But what exactly allows for the adaptation of stress to result in bigger muscles? The standard answer: The muscles adjust to heavy weights and as a consequence enlarge and increase in strength. You may think the scientific explanation of the muscle building process is more elaborate and complex, but in actuality it's even simpler-no one knows for sure.

This ambiguity regarding muscle hypertrophy has led to the dozens of available training programs, all promising the "best" results. The irony - no particular exercise routine can possibly be the best because the body will adapt to any form of stimulus sooner or later. Mother Nature is a lot smarter than any scientist or exercise guru. She s always one step ahead.

Whenever you hear someone praise a new technique or tell you he found a personal trainer who jump-started his gains, all that really happened was he did something different. The newness of the stimulus produced results. Eventually, the body will adapt to the new method of working out and progress will stall again.

To establish change most bodybuilders use what is known as periodization, which is basically the concept of alternating between periods of heavy weight, low-rep training and lighter weight, high-rep training. Exercises are also varied in an effort to keep your routine fresh.

Regardless of how many changes you make, what may be the biggest factor in the process of muscle growth is often ignored. The important ingredient is the amount of time the muscles are placed under tension. Some believe the time-under-tension theory is the only factor which matters. They could very well be right.

Follow me for a moment. When lifting a weight the muscle goes through a range of motion. Within each nano-inch of movement hundreds of fibers come into play. After completing a set of, let's say, 10 reps each of those fibers has been stressed for a specific amount of time.

Now, let's suppose that set took 30 seconds to complete. What difference would it make if only 5 reps were completed in that total time? Wouldn't all the muscle fibers have received the same amount of stress? Even though the muscle contracted half as many times, the period when the fibers were stressed was twice as long. Will this change produce as much muscle growth? Less? More? Is 3 sets of 10 repetitions much different than 6 sets of 5 reps? It's hard to say for certain. There are too many variables to accurately gauge motor recruitment, but the theory does pose some intriguing speculations, doesn't it?

One argument against the time-under-tension method is how isometric exercise (when tension is developed but you have no change in the length of the muscle) places strain on a muscle for a designated amount of time, yet the results gained from this type of workout have been proven to be sub-par to that of weight training. The comparison, however, is unfair. Since isometrics work a muscle in a static position all the fibers don't come into play. You need to perform this type of activity in every range of a muscle's movement and, to my knowledge, not too many people have attempted such a program. (Although I would be interested to hear about the results.)

Another angle to the time-under-tension principle has to do with powerlifting. If a powerlifter executes only 2 or 3 reps the length of the set is only a couple of seconds. How can that lead to any strength and muscle gains? The answer: The lift is performed many times throughout the workout. If he does 20 sets of five-second lifts that's 100 seconds that the muscles have been under tension, which is approximately 3 "normal" sets. This amount is a bit on the low-volume side, but as you know powerlifting is supposed to develop strength, not muscularity.

Realize also those 100 seconds are at ultimate intensity. Incidentally, although similarities exist between bodybuilding and strength training, for optimum development in one or the other, you need to concentrate on that form of training.

By following the theory that growth results from the duration a muscle is under stress, why not incorporate this facet of training in-to both your heavy and light training periods? Try a few sets in the following manner and you may be surprised to find how deeply this technique hits the muscle.

How to Incorporate time under tension into your routine


» Choose a single exercise for a specific bodypart, such as a barbell curl.

» Take a weight you would normally use for 8 reps.

» Time how long it takes to complete the set.

» Now, using a clock with a second hand, perform a single rep slow enough you take as long to complete it as you did to do 8 reps.


You can use the same technique with a lighter weight:

» Grab a weight conducive to getting a pump -about 10 to 12 reps.

» Complete the set and time it.

» Instead of doing 10 to 12 reps, try to stretch only 5 reps into the same period of time.

» Shoot for the full amount of sets, but make each rep super slow.


o Perform as many reps as possible (in a controlled fashion) in a set amount of time.

» Do the concentric portion of the exercise in an explosive manner and the eccentric (re-turn) portion slowly.

» Reverse the above procedure.

» Use a metronome. (One can be purchased in any music store. You don't need anything elaborate, just something that will tick in time.) Count the amount of ticks it takes to complete each phase of a rep and try to match it every time. You'll be surprised how much this process makes you concentrate on your technique.

By using the time-under-tension method you can accurately determine if training at various speeds is preferable to doing sets at a consistent rhythm. One factor is certain -changing the speed is another variable in the training process and variety is what keeps the gains coming.

The next time you work out experiment with time under tension. Keep a log of the length of each set so you'll know exactly how long you actually exercised. In this way, whenever you try a new routine or use different poundages, you'll have a better under-standing of how hard you're really working. You'll also add another dimension to your training program. While you're at it, there's a good chance you'll wind up with more muscle. Perfecting the time-under-tension principle may take a little more work, but your time will be well spent.

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