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Intensity is everything - build new muscles with the help of intensity techniques

Intensität ist alles – Baue neue Muskeln mit Hilfe von Intensitätstechniken auf

Bodybuilder and competition trainer Cliff Wilson explains the concepts of training, load and volume to help you optimize your training and maximize your results.

How varying intensity techniques can lead to new muscle growth

All my life I wanted to have a cool nickname. In high school, I even went so far as to try to give myself the nickname C-Dub. That was definitely not a proud moment for me. But when I was talking to a friend at my gym recently, I learned that the majority of the people at my gym already had a nickname for me.

I was thrilled at first, but that changed when I found out what my nickname was. My awesome new nickname is now "That crazy guy." As in, be careful, get out of this crazy guy's way when he's doing walking lunges. Apparently, people at my gym think I'm crazy because of the level of intensity with which I work out. This isn't quite the cool nickname I had envisioned, but I'll take it.

I don't expect the average gym-goer to understand the need for ever-increasing intensity, but too many bodybuilders and competitors in the figure class don't either. It doesn't matter how advanced you are. If you always do 4 sets of squats of 10 reps with the same weight on leg day and make no effort to increase the intensity of your training sessions, then your body will make no effort to increase the amount of muscle mass.

Just because a training session gives you a pump does not mean that you have stimulated new muscle growth. This is particularly important for experienced exercisers. After an exerciser has trained consistently for many years, it takes extreme measures to achieve significant improvements.

When it comes to training, the word intensity can have different meanings. When putting together a training program, intensity must be increased and decreased in all forms to achieve gains without overtraining. Knowing the body's response to varying degrees of intensity will allow you to use many different methods to increase your muscle growth.

The load (the training weight)

The load - also known as the training weight - can be expressed as a percentage of the 1RM weight (the maximum weight with which you can perform one repetition of an exercise with clean form). Training with weights of both light and heavy weights will induce hypertrophy, which is the primary mechanism for increasing muscle size (1). A common debate among exercisers centers on whether it is better to train with lighter or heavier weights.

Training with weights at around 85% of 1RM weight until muscle failure - or close to muscle failure - has been shown to best stimulate hypertrophy (1). Although the greatest gains can be observed when using moderate weights, lighter and heavier weights must be used to maximize the full muscle building potential. This is due to the fact that there are two different types of hypertrophy that occur during resistance training (2).

The first is called myofibrillar hypertrophy and is an increase in the number and size of actin and myosin filaments in muscle tissue (2). This type of hypertrophy is accompanied by strength gains as it involves an increase in contractile tissue (2). Although you can't completely isolate one type of hypertrophy from the other, myofibrillar hypertrophy primarily occurs during training with heavy weights and low repetitions (2).

Those who have just started training will experience tremendous gains in strength with only small gains in hypertrophy regardless of the weights and repetition ranges they use. These strength gains can be primarily attributed to neural adaptations, as previously untrained individuals may have difficulty activating their motor units (1).

The second type of hypertrophy is called sarcoplasmic hypertrophy and represents an increase in sarcoplasmic and other non-contractile proteins within the muscle cells and is primarily induced by training with light weights and high repetitions (2). This type of muscle growth, although not accompanied by strength gains, is the primary reason why bodybuilders tend to be more muscular than strength athletes.

To achieve continuous muscle gains over an extended period of time, progressive overload must be used. Simply put, you need to move heavier weights if you want your muscles to keep growing. This is true regardless of what repetition ranges and weights are used. Increasing your maximum weight for both high and low repetition ranges should be the ultimate goal for any training program, as this is the best way to ensure continued growth.

One of the reasons that moderate repetition ranges produce the greatest gains in muscle tissue could be related to the fact that moderate weights allow the use of a relatively heavy weight with more time under tension. This combination seems to allow for a balance between large amounts of myofibrillar and sarcoplasmic hypertrophy.

Too many bodybuilders still mistakenly believe that heavy weights with low repetitions should be used to build muscle and that light weights with high repetitions should be used to burn fat. Too often I meet new clients who have been training with this misconception for years. Using only light weights during contest prep is a great way to lose muscle, and in addition to that, you're missing out on a lot of potential muscle growth if you never train with lighter weights during the bulking phase. A solid training program should include heavy, moderate and light weights to maximize overall muscle hypertrophy.

This also applies to contest preparation and will help you maintain your muscle mass or even build muscle while dieting. Training with weights should build and maintain muscle tissue. Use cardio training for fat loss. When discussing load and intensity, it is most important to note that each set is performed to a point that is at least very close to the point of muscle failure. A light weight that is only used for a few repetitions will not accomplish much. If your training session is not demanding, then you are not training at high intensity.


The term volume in training refers to the total amount of work done in a given training session. However, the term volume is most commonly used to describe the number of sets performed during a training session. Training volume has been a very sensitive topic for many in the bodybuilding community for years.

Many High Intensity Training (HIT) advocates such as Arthur Jones and Mike Mentzer claim that 1 to 4 sets to failure per muscle group are needed to stimulate maximum muscle growth, while others, including Arnold Schwarzenegger, claim that maximum muscle growth can be achieved by performing 20 to 25 sets per muscle group. With such conflicting views on training volume, it can be difficult to know how much volume is appropriate.

Although high-volume and low-volume training programs have been shown to be effective in practice, if maximizing muscle growth is the primary goal, high-intensity, high-volume training programs must be used. Although it has not yet been fully proven, studies conducted in humans provide indirect evidence of hyperplasia following high-intensity, high-volume strength training (3). Hyperplasia is another form of muscle growth that differs from hypertrophy. Hypertrophy is an increase in the size of existing muscle cells, whereas hyperplasia is an increase in the number of muscle cells.

The endocrine system, which is responsible for the release of hormones within the body, is also sensitive to training volume. Varying the amount of work performed from training session to training session can be used to manipulate the endocrine system and create an optimal hormonal environment. Using high volume with multiple sets of multiple exercises can increase serum testosterone levels and optimize adrenal hormones (4).

Although high-volume training can be very effective, it comes with the risk of overtraining. Additional volume can increase the release of anabolic hormones, but adding too many sets to training too often can have the opposite effect. Volume-related overtraining will ultimately lead to a reduction in the release of lutenizing hormone and lower levels of free testosterone (5).

With volume-related overtraining, cortisol also becomes a problem. Small increases in cortisol levels during training can lead to growth hormone release and signal the body that repairs need to be made, but if volume training is continued for too long and not used cyclically, then this can cause cortisol levels to rise too high and remain high, which can lead to a chronic catabolic response to cortisol.

Apart from the risk of overtraining, high-volume training has another disadvantage. Resistance training in general has been shown to upregulate androgen receptors for 48 to 72 hours after training (5). Unfortunately, high-volume training will initially downregulate androgen receptors before upregulation occurs.

This initial downregulation can be prevented by consuming a protein/carbohydrate mix before and after training. If you've read my previous articles, then you'll already know the benefits of a protein/carbohydrate mix before and after training. This is just another good reason to include these shakes in your nutrition plan.

When it comes to the topic of training volume, it's best to keep an open mind. Too many people are caught up in the mindset that they should never do more or less than a certain amount of sets. Keep in mind that increasing the volume of your workouts is one of the easiest ways to get into a state of overtraining, but that increasing the volume is also a way to stimulate new muscle growth. High volume phases should be used to maximize muscle growth, but low volume phases must also be incorporated into the training program to ensure that your body can keep up with the demands you place on it.

Conclusion on intensity, load and volume

When determining the level of intensity for an effective training program, volume and load are the first two things that need to be addressed. Incorporating varying levels of both weight used and number of sets can be difficult, but doing so will allow you to prevent overtraining and maximize your genetic potential. These variations can also fluctuate from one muscle group to the next depending on your individual weak points.

Once you have determined the load and volume of your training, there are two more points that we will look at below.

The rests between sets

The pauses between sets are something that most bodybuilders rarely change. As with repetition ranges and the number of sets used during training, most exercisers find what they like best when it comes to rest length and tend to stay within their comfort zone. However, rests between sets are another tool that can be used to increase the intensity of your workout.

The length of rest between sets is directly related to how much energy your muscles will have available when the next set begins. It takes about 3 minutes for your muscles to recover after a set to the point where they have nearly 100% of their ATP and CP (creatine phosphate) levels, which are the two primary sources of energy for working muscles.

This will allow the use of near maximal weights on almost every set. For this reason, strength and power athletes rest long between their training sets. Long rest intervals in conjunction with heavy weights should be incorporated into every bodybuilder's program, as this will help achieve the ultimate goal of progressive overload.

Shorter rest intervals between 60 and 90 seconds allow for 85 to 90% recovery of ATP and CP levels (5). Shorter rest intervals have been shown to have a greater impact on growth hormone levels than longer rest intervals. Keeping rest intervals short works well when training for hypertrophy with moderate to light weights and high repetitions with higher volume. Studies show the most dramatic increase in growth hormone levels with sets of at least 10 repetitions combined with rest intervals of 40 to 60 seconds (7).

Shorter rest intervals have the advantage of allowing you to do a higher volume per training session for a shorter duration. Growth hormone and testosterone levels reach their highest levels after 60 to 90 minutes of training and then drop again quickly. If training continues for too long after reaching this point, hormone levels can drop below normal at rest and even remain below normal for several days (8, 9).

I'm not a fan of staring at the clock until the start of my next set, but too often I see bodybuilders with extremely variable rest intervals. Too much chatter and too much texting on the cell phone are the main culprits here. It's simply not necessary to change your Facebook status from "training straight biceps" to "training straight triceps" during training.

It's unacceptable for soccer or basketball players to talk or text while training - so why should it be any different for bodybuilders? All this distraction will rob you of your focus and intensity. There is no need to use a stopwatch, but timing your rests appropriately between sets will make it necessary for you to focus on what you are doing. Leave the distractions in the locker room and your workout will reach a new level of intensity.

Muscle failure

Even though training to muscle failure is different from the other forms of intensity we've talked about so far, I think it needs to be addressed here. When you go to the point of momentary muscle failure, you can use both light and heavy weights. When performing a set this way, you simply continue the set until you reach the point where you can no longer perform another repetition in good form without assistance. When most people think of a really intense workout, the first thing that comes to mind is performing a lot of sets to muscle failure.

This is the reason that whenever the topic of training intensity is discussed, training to muscle failure is often a point that is emphasized. Like the other forms of increasing intensity, training to muscle failure is a very hotly debated topic in the bodybuilding community. Many advocates of training to muscle failure believe that a set that is not performed to muscle failure is a wasted set. Others avoid performing a set to muscle failure because they fear it could lead to overtraining. Both groups have valid concerns that need to be addressed.

The rationale for using training to muscle failure is that if some motor units exhaust and fail during a set, other motor units must be recruited to continue the activity. The problem with this rationale is that, given this rationale, one should be able to train to muscle failure with very low resistance and achieve large gains in hypertrophy and strength.

As already mentioned, this is not the case in reality. It is well known that moderate to heavy weights must be used to achieve maximum hypertrophy (10). Many studies have shown that training to muscle failure produces gains that are superior to the gains that can be achieved by not training to muscle failure. Although it has been shown that training to muscle failure is more effective, stopping the set shortly before reaching muscle failure can also produce large amounts of muscle growth.

This is due to the fact that overload is the primary determining factor when it comes to muscle growth - not muscle failure itself. Continuously moving heavier and heavier weights across all different repetition ranges will overload the muscles and force adaptations. This is easier said than done, as anyone who has been training with weights for many years knows. Increases in strength do not always occur at a constant rate, but rather in spurts with periods of stagnation. This is one of the reasons why training to muscle failure is effective.

At a certain point in training, optimal gains can be achieved by performing sets to the point of momentary muscle failure (11). Training to muscle failure may also be the best way to increase the intensity of a training session. As soon as a training session begins, testosterone and growth hormone levels rise during the first few minutes.

How much the levels of both hormones increase is directly related to the intensity of the workout. The intensity of the workout is the primary determinant of the amount of growth hormone your body will release, while the duration and volume of the workout have little to do with growth hormone release(12). For this reason, training to muscle failure can be an excellent way to increase the intensity of your training and use the induced release of anabolic hormones to your advantage.

One disadvantage of training to muscle failure is that it is very demanding on the central nervous system. The nervous system is responsible for activating motor units during training. Although muscle tissue may be able to recover from many sets performed to muscle failure, this is unfortunately not the case with the nervous system. Some programs in which all work sets are to be performed to muscle failure will definitely lead to overtraining.

Training programs must therefore include both sets performed to muscle failure and sets performed close to muscle failure in combination with phases during which no set is performed to muscle failure. Many of the benefits of training to muscle failure can be achieved by performing a set close to the point of muscle failure. Performing the set 1 to 2 repetitions before reaching muscle failure will allow sufficient stimulation of the muscle fibers while sparing the nervous system a lot of stress.

It is important to note in this context that overtraining caused by high intensity has completely different effects than overtraining caused by high volume. The main difference between these two causes of overtraining is the effect that overtraining has on the endocrine system. In high-intensity overtraining, catecholamines - also known as fight or flight hormones - show an increased response to exercise. And although overtraining induced by too high a training volume will lead to a reduction in testosterone levels, overtraining induced by high intensity has no effect on testosterone levels (13).

The ultimate goal of any training program is to push your body as hard as possible without causing overtraining. Bodybuilders are always at the threshold of overtraining and it seems that the effects of exceeding this threshold are less devastating if a higher intensity and less volume is used.

Let's summarize everything

These techniques for increasing intensity are different from descending sets or supersets. Although the latter are excellent techniques for increasing intensity and should definitely be used from time to time, the principles of load, volume, rest intervals and muscle failure need to be adapted in your training with weights to ensure consistent growth over many years.

These aspects of training are not independent of each other and if one is adjusted, all others must be adjusted accordingly. Appropriate levels of intensity will vary greatly from person to person depending on genetic predisposition, diet and use of performance enhancing compounds. Those who have chosen to remain steroid-free bodybuilders have chosen a more difficult path.

Steroid-free bodybuilders need to be much more aware of the effects of each of these points, as banned performance-enhancing compounds can compensate for many errors or deficiencies in training. Make sure you take a close look at the intensity level of your training. In my experience, most exercisers convince themselves that they are exercising more intensely than is actually the case.

Many exercisers have no problem going from set to set with very short breaks between sets. Many exercisers have no problem moving heavy weights or performing many sets. However, you will also find that very few people have the determination to go all out in every aspect of the word "intensity". Doing so requires a level of planning and pain that most are unwillingÄ to take on.


  1. Chandler, T. J., Brown, L. E., Conditioning for Strength and Human Performance, 2007, 52-53p.
  2. Zatsiorsky, V. M., Kraemer, W. J., Science and Practice of Strength Training, 2006, 50p.
  3. Abernethy, B., The Biophysical Foundations of Human Movement, 2005, 151-152p.
  4. Baechle, T. R., Earle, R. W., Essentials of Strength Training and Conditioning, 2008, 63p.
  5. Baechle, T. R., Earle, R. W., Essentials of Strength Training and Conditioning, 2008, 114-116p.
  6. National Academy of Sports Medicine, Optimum Performance Training for the Health and Fitness Professional: Course Manuel, 2008, 332p.
  7. Baechle, T. R., Earle, R. W., Essentials of Strength Training and Conditioning, 2008, 58p.
  8. Garret, W. E., Kirkendall, D. T., Exercise and Sport Science, 2000, 152p.
  9. Kreider, R. B., Fry, A. C., O'Toole, M. L., Overtraining in Sport, 1998, 153p.
  10. Frohlich, M., Pruess, P., Current Results of Strength Training Research: An Empirical and Theoretical Approach, 2005, 80p.
  11. Fleck, S., Kraemer, W., Designing Resistance Training Programs, 1997, 20p.
  12. McArdle, W. D., Katch, F. I., Katch, V. L., Essentials of Exercise Physiology, 2006, 410-411p
  13. Chandler, T. J., Brown, L. E., Conditioning For Strength and Human Performance, 2007, 119p.


By Cliff Wilson

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