Many people combine strength and endurance training to improve these skills and performance, and many sports require such a combination.

The inclusion of strength training (to gain strength and / or hypertrophy ) combined with resistance training in a single program is known as concurrent training.

Numerous scientific studies have found that the simultaneous development of muscle strength and cardiovascular endurance capacities can lead to interference in adaptations, especially adaptations of force, which is why it is necessary to consider and apply strategies that minimize the effects of concurrent training of strength and endurance.

The strategies that I will expose in this post are taken from scientific articles, which you can read here and here .

The interference phenomenon

There is talk of an interference phenomenon when working force and resistance together. This interference will be greater or lesser depending on the design (exercises used, volume, intensity, etc.), time duration and type of subjects (sedentary vs sportsmen).

When we apply a training stimulus, either of strength or of strength, in the organism there will be a series of changes and adaptive responses, which in the case of concurrent training of both capacities can be opposed.

That is, because resistance and resistance training produces distinct, and often often opposing , adaptive mechanisms, the concurrent development of both capabilities within the same training regimen can trigger a conflict of adaptations.

Mechanisms that can cause interference

In the simultaneous development of muscle strength and cardiovascular endurance capabilities, numerous studies in the scientific literature have detected interference in adaptations of muscle strength and power. Among the interference mechanisms of the so-called concurrent training include:

• The accumulation of residual fatigue produced by previous training on the neuromuscular system.
• The depletion of muscle glycogen reserves .
• Transformations in the types of muscle fibers IIb to IIa and IIa to I.
• Overtraining caused by imbalances between the training and recovery processes.
• Inhibition of protein synthesis after resistance training, with the consequent decrease in the cross section of muscle fibers and a reduction in muscle capacity to generate tension .
• Chronic hypothesis : muscle tissues can not adapt metabolically and morphologically to strength and resistance training simultaneously.
• Acute hypothesis : an increase in residual fatigue that is favored by resistance training and that lasts over time affects the tension capacity of the muscle. Therefore, the longer the concurrent training of strength and endurance lasts, the more affected the force work will be.

Possible positive adaptations with concurrent training

On the contrary, several investigations have also shown that the simultaneous or concurrent training of strength and resistance produces positive adaptations in sedentary subjects or with little experience in training.

In cyclic and team disciplines (for example: canoeing, rowing or rugby ), it has also been shown that concurrent training can be beneficial in improving specific performance.

Some of the mechanisms that seem to be responsible for these benefits of concurrent training for specific performance would be:

• The increase in strength, which seems to improve mechanical efficiency, muscle coordination and motor recruitment patterns.
• The global increase in force can facilitate changes and corrections in the technical model of competition.
• The increase in muscle strength and coordination can reduce the relative intensity that each cycle of effort is for the athlete and, therefore, be more resistant over time.

In summary, the discrepancies observed in the studies that have examined the interference phenomenon of concurrent training in sedentary youngsters or in trained athletes are possibly related, as we have commented previously, with the initial level of performance of the subjects, the types of exercises used, the volume, intensity and frequency of training and the distribution of the sessions, among other aspects.

Bearing all this in mind, it is necessary to consider and apply strategies that minimize the effects of concurrent strength and endurance training.

The seven key strategies you must know to maximize your concurrent training (strength and endurance)

1. Periodiza

An adequate periodization of the training, with a high concentration of load directed to a reduced number of objectives per training phase will allow producing positive adaptations and minimizing the effects of interference.

That is, do not try to work and improve all the time (hypertrophy, high intensity resistance work, training more oriented to the improvement of strength, resistance to low intensity, etc.).

Let’s put few objectives per phase and work to achieve them (the best and worst combinations of strength and resistance will be explained in later points).

2. Do not reach muscle failure

Avoid reaching muscle failure in strength training will reduce part of the metabolic and hormonal stress that comes with this training and facilitate a better and faster recovery, plus you will not improve more your strength and your gains in muscle mass to reach muscle failure (more than checked).

3. Distance your strength and resistance training aimed at the same muscle groups

Distance training sessions of strength and resistance aimed at the same muscle groups will facilitate their recovery and improve the adaptation to training stimuli.

For example, better to perform leg strength training and race training (resistance) on separate days and if you can not, distance the sessions as much as possible (the best order we will see in subsequent points).

4. Resistance in the morning and strength in the afternoon as best option

Any high-intensity resistance training session should be done early in the day. Next, a recovery period of at least three hours should be administered  so that the activity of important enzymes related to the resistance and its improvements (AMPK and SIRT1) can return to the basal levels, before performing the strength exercise.

This suggestion is based on the fact that the activity of an important enzyme related to the improvement of resistance, such as AMPK , increases rapidly and then returns to baseline levels within the first three hours after a high-intensity exercise., while the activity of a complex protein that controls protein synthesis, such as mTORC1, can be maintained for at least 18 hours after strength exercise.

Therefore, the most practical approach to combining strength and strength training within the same day is probably a resistance session in the morning , followed by a strength training in the afternoon .

5. Muscle hypertrophy and high intensity resistance, bad combination

The combination of strength training aimed at muscle hypertrophy with high intensity resistance training seems to be inadvisable for generating a high degree of interference.

This is so because the development of both capacities produces totally opposite peripheral type adaptations and prevents the organism from an optimal and simultaneous development of both performance components.

That is to say, among the peripheral adaptations to strength training aimed at muscle hypertrophy are the increase in contractile protein synthesis that leads to an increase in the size of the fiber and the cross section of the muscle, as well as an increase in glycolytic enzymes., in addition to a reduction in capillary and mitochondrial density and considerable metabolic and hormonal stress at the cellular level.

On the contrary, high intensity resistance training (intensities close to VO2max ) produces peripheral adaptations as a priority, but in this case these adaptations are the increase in muscle glycogen reserves , the increase in capillary and mitochondrial density and the increase in the oxidative enzymes.

6. Muscle hypertrophy and moderate intensity resistance, a better option

The concurrent development of resistance training of moderate intensity and strength training via muscle hypertrophy in this case has a lower degree of interference since there are no opposite adaptations to training, as if they occur, as we have seen in the previous point, with hypertrophy training and high intensity resistance.

7. Strength training immediately after a session of low intensity resistance (for greater adaptation in resistance)

To improve the resistance response to low intensity endurance training sessions and provide a strong force stimulus we can consider performing strength training immediately after low intensity, non- exhaustive resistance sessions . And I repeat, not exhausting.

Performing a strength session immediately after a low intensity resistance session results in a greater stimulus for resistance adaptation than the low intensity resistance session alone, and the low intensity session will not affect the signaling pathways that regulate the strength gains.

These are some of the important strategies that we must consider if we are of the people who perform strength training as much as resistance. It is a topic that is still being studied, so I am sure that in the future there will be more strategies that will help us even more.

Soon I will release an article with some nutritional strategies for people who perform resistance and strength training, so the sum of the training strategies in this article plus the nutritional strategies that I will inform soon will allow us to get more out of our training and get a better performance.