n a nutshell: the higher the stimulus, the greater the signal to the body to build muscle and adapt. However, this also means the higher the exhaustion after the training the higher the recovery time required. This is exactly why high intensity (HIT) strength training is the most effective and time-saving form of strength training, because it enables the greatest possible stimulus in just a few minutes of training. But it is important to understand that the long recovery time triggered by the intensive training also means that you should actually only train every 5-7 days. Depending on the genetic disposition and state of training, even longer recovery times are required. That means that an intensive strength training only takes a few minutes a week if done correctly.
In training, the effect of a stimulus is determined by how many muscle fibers are activated during the workout. If only a few fibers are addressed, this corresponds to a low stimulus, if many fibers are addressed, one speaks of a high stimulus. Science shows that HIT strength training sets the highest possible stimulus for the body. And when done correctly, it allows us to fully fatigue all muscle fibers. Studies clearly show that the higher the stimulus, the stronger the signal for the body to adapt and to build strength and muscles. According to studies, one set per exercise is completely sufficient to achieve the desired effect on strength and muscle gain (and even endurance).
Our body always tries to save energy whenever possible. This means that our brain only activates the amount of muscle fibers that is really needed to generate a certain amount of force. Roughly speaking, there are three types of muscle fibers: Slow Twitch, Intermediary Twitch and Fast Twitch (in the exact scientific categorization there are four types, each with two subcategories, but this rough categorization is sufficient for understanding). It is often wrongly assumed that the term refers to the contraction speed of the muscle and thus to the speed with which a weight can be moved or a movement can be performed. In fact, the term only refers to how quickly these muscle fibers fatigue, namely slow, medium or fast. The slow-fatiguing ones recover quickly and the fast-fatiguing ones take a long time to recover, while the medium-fatiguing ones lie somewhere between the two extremes. The slow-fatiguing muscle fibers can exert less strength than the fast-fatiguing muscle fibers. Only if we manage to fatuige all muscle fibers will we get the full metabolic effect.
When training with weights, you have to choose a medium weight for HIT training. The reason is that you have to get through the so-called sequential recruitment of muscle fibers. First the Slow Twitch get fatigued, then the Intermediary Twitch fibers start to work and finally the Fast Twitch jump in to support. The problem with traditional weights, however, is the determination of the correct weight: If the weight is too low, the slow twitch fibers may not even be exhausted and only the intermediate twitch may follow. But before these are exhausted, the slow twitch fibers have already temporarily recovered (this happens after c. 60-90 seconds) and help out again before the fast twitch fibers can be addressed. This means, none or not all of the intermediary and / or fast twitch muscle fibers are reached. If the weight is too high, so that you can only do one or two repetitions, then all muscle fibers are addressed at the same time. The problem, however, is that the Fast Twitch fatigue very quickly. And after that, only the Slow and Intermediary Twitch are available because they fatigue more slowly. However, the Slow and Intermediary Twitch cannot generate enough force to move the weight at all. That means the training is over before the intermediate and slow twitch muscle fibers are fatigued. An optimal weight leads to the fatigue of all muscle fibers. This has to happen within 60 to 90 seconds before the Slow Twitch can come back to help and have recovered temporarily.
This is where the AURUM machines with adaptive resistance have the decisive advantage over weights. All muscle fibers are addressed from the start. As soon as the Fast Twitch fibers are fatigued, only the Slow and Intermediary Twitch are available, but the strength that we have to face adapts directly. After the intermediaries have failed, the slow twitch can only exert some force for a few seconds, but again the weight adapts so that they can also be completely fatigued. But not only that. Have you ever noticed that it is more difficult for you to press the weight upwards (concentric or positive movement) than to lower the weight (eccentric or negative movement)? This is a physiological condition of our body. Our machines reflect the force that is put into them at all times, which means that the eccentric movement can be fully utilised. With traditional weights you are always limited by the concentric movement, otherwise the weight is too heavy to perform this movement.
Very good results can be achieved with traditional weights with a HIT training protocol, but the stimulus to build muscle, bones, tendons and ligaments is much more potent with adaptive resistance training. The desired stimulus threshold is therefore reached far more optimally and quickly than with traditional weights. At the same time, the AURUM training with our new machines is even safer because you can never choose the wrong weight. The greatest risk of getting injured during sports in general or during strength training arises when movements are carried out too quickly. The reason behind it is that kinetic energy is generated by momentum. With momentum larger forces can be applied. That is why professional weightlifters work with momentum or fast movements. The problem: the forces can be so high that they exceed the load-bearing capacity of the joints, muscles and tendons. This can never happen with AURUM training. The machine always sets the speed and the exercises are performed slowly and you control how much force is applied and this without momentum and kinetic energy. In addition, all muscle fibers are fully exhausted. Because the energy always comes from its own power and is not partially supported by kinetic energy. The AURUM high intensity strength training is therefore progress along three dimensions: more effective, more time-efficient and safer. The machine always sets the speed and the exercises are carried out slowly and therefore only on their own, that is, without momentum and kinetic energy. In addition, all muscle fibers are really fully exhausted. Because the energy always comes from your own power and is not partially supported by kinetic energy. The AURUM high intensity strength training is therefore progress along three dimensions: more effective, more time-efficient and safer.
Even with HIT training, many sports experts repeatedly recommend that several sets should be performed per exercise. However, the specialist literature suggests that a set that fatigues all muscle fibers is completely sufficient as a stimulus. A study with amateur weight lifters, for example, in which they had to complete different sets, found that one set per exercise was as effective as two and four sets to improve muscle size, strength and explosiveness in the upper body (1).
The physiologists R.N. Carpinelli and R.M. Otto conducted a meta study in which they searched the entire known literature for studies in which the efficiency of a one set strength training was compared to that of several sets. The results show that performing multiple sets in total does not result in any additional improvements. The underlying specialist literature clearly shows that a single set is fully sufficient. Only in two of the forty-seven studies examined an advantage with a multiple set approach was found (and also only a negligible optimization in those studies was observed) (2). (Important: No AURUM machines were used in these studies, only weight-based systems - due to the advantages described above it is only logical to assume that the results can even be exceeded with the new AURUM technology)
Other studies also confirm this conclusion. Researchers who examined a strength increase of seventy-seven subjects who did one set, two or three sets of a specific upper body exercise over a period of ten weeks all showed a similar improvement in their muscle strength (3). Another study compares the strength increase in thirty-eight subjects over 14 Weeks, each of which had to complete one set or three sets of an exercise for the lower body. Similar improvements in lower body strength have also been documented here (4).
A study published in the journal Medicine and Science in Sports and Exercise found that one set of high-intensity resistance training is as effective as three sets to increase both isometric torque and muscle diameter in untrained adults for knee extension and flexion (5).
A one set approach that manages to fatigue all muscle fibers is fully sufficient as a stimulus to trigger the growth of muscle mass and an increase in strength. Additional sets do no harm, but in this context they are a waste of time.
In general, the higher the stimulus for the muscle, the longer the recovery time required. Training every 5-7 days at high intensity is not only sufficient, more frequent training is even counterproductive and can lead to a reduction in strength and muscle mass. 50% of training success is related to giving the body enough time to recover and relax. The remaining 50% depend on the intensity of the training stimulus during the training, which is described in the section before.
We have to distinguish between two aspects of recovery. The temporary recovery of the muscle fibers during or shortly after training as described above. The other is the recovery of the energy reserves and resources that are used up in a workout and determine the recovery time required.
You can say figuratively that with every workout you dig a hole (you damage the muscle). This catabolic state of breakdown and weakening must be balanced with an anabolic state of buildup and recovery. If you dig a hole by exposing your muscles to a training stimulus, you have to allow enough time to fill up the hole again (recover) and reinforce it with additional building material (the so-called super compensation, in which you build up more muscle mass than before to increase you general strength level). If you continue digging before the hole is filled, you will not form a hill, but will dig an ever deeper hole. Therefore, you should not exercise before the body has completely recovered and has also formed additional muscle tissue. But how long does that take on average?
The growth of new muscles can be compared to a cut or a burn. The injury is a stimulus that activates the body's growth and repair mechanism, which in turn heals and repairs the damaged tissue. It usually takes a week or two to heal a cut or burn. Building muscles takes much longer than healing the skin after a burn, because the epithelial cells on the body surface can regenerate relatively quickly compared to muscle tissue, which is formed from another type of stem cell and requires a significantly longer healing time.
But let's go a little further into the scientific details of what happens in the body after training. The medical literature clearly shows that the more the muscles contract, the more damage there is at the cellular level. 6) That means, the more intensive the training, the more time the body needs for the repair and growth of the tissue. The repair of the muscle tissue makes the body stronger. 7) The workout causes a short-term damage to the muscle fibers, which mostly happens in the lowering phase of an exercise (the so called eccentric movement), not in the lifting phase. 8) In the twenty-four hours after training, there is an inflammatory state in which all white blood cells (neutrophil granulocytes) increase and are transported to the injured tissue.9) During the first day, lyosomes are produced - these are enzymes that break down and metabolize damaged tissue - which intensifies the inflammatory process. 10) In the following days, other cells (macrophages) become active, which in response to the inflammation synthesize further messenger substances and help to increase the number of lyosomes. One of the messenger substances is the hormone prostaglandin E2, which is said to make the nerves of the muscles more sensitive to pain, which partly explains the muscles soreness that start 24 to 36 hours after training.11) These inflammatory processes initially damage the muscles and can still be felt several days after the workout.12) After the inflammatory reaction is over, the first signs of tissue regeneration or muscle building become noticeable.13 First, the muscles return to their original size as before training. If you give them more time, they will grow even more (super compensation). The duration of this process depends on the intensity of the training stimulus and the associated damage that the muscles have suffered.14) As a rule, this period is between 5 days (if it goes quickly) and six weeks.15) In addition to the previous literature - what happens in the body at the microscopic level - a whole series of studies have dealt with the frequency of training itself. All of these studies concluded that training once a week achieves all the benefits that can be achieved with more frequent training and that more training does not serve an additional purpose.16)
A study by the Utah State Strength Laboratory, for example, shows that performing just one set on the leg press once or twice a week statistically leads to a comparable increase in strength. This study is even based exclusively on female test subjects. That means it can be ruled out that the effects only apply to men (17). It should be emphasized that these and other studies only looked at relatively short periods of time (8 weeks). Based on the experience of the Body by Science authors with over 150,000 workouts with their customers, they believe that if you extend the studies over ten to 12 weeks, you will see clearly negative effects if two or more workouts per week are completed per week. The phenomenon has even been demonstrated in two clinical trials that were carried out eight years apart. In the controlled experiments, the researchers examined the developmental progress of two groups of subjects - one group trained three days a week, the other two days a week. The researchers then reduced the training frequency so that each group trained one day less per week. The researchers found that all trial groups made significant progress after reducing their training frequency. (18). Similar results can also be seen in other studies. Here, too, test subjects of various ages took part and the frequency of training was reduced by the researchers. Here, too, it was found that the performance of the test subjects improved considerably after the training frequency was reduced.
Either way, at best, more workouts will have the same effect as one workout per week. So why waste a lot of time on strength training?
At AURUM we do so-called compound exercises, which simultaneously address several muscle groups. The optimized resistance with the AURUM training machines creates an optimal exhaustion of all involved muscle groups. The 6 compound exercises train all muscles of the human body.
The AURUM workout consists of the so-called Big Five plus an exercise that additionally strengthens the lower back. The entire program consists exclusively of so-called compound movements, i.e. several joints move at the same time, which means that several muscles are used simultaneously in each exercise. In the Big Five approach, 3 core exercises (leg press, chest press and lat pulldown) train all the major muscle structures of the body. To this basic framework come rowing and overhead presses, especially strengthening the shoulders with shoulder blades and shoulder muscles. Together with the exercise for the lower back, the muscles that should be strengthened in our frequently sedentary society are now specifically addressed. The Big Five are large, but simple movements that are so simple in terms of movement that they can also be performed with weights by people of average fitness and even here the muscles are well stimulated. The Big Five exercises have proven themselves over the years from experience with over 150,000 training sessions by the authors of Body by Science. Already during high intensity training with weights, enough muscle stimulus is set in all muscle groups to sufficiently fatigue all muscles involved. With the AURUM training with adaptive resistance, this is even increased and you can be sure that an optimal stimulus is set for all muscles involved.