SQUATS, WHAT CAN CHANGE WITH ELECTROSTIMULATION

Squats with electrostimulation

The squat is one of the most basic exercises in any routine. Your FAST coach was probably the first thing he taught you to do correctly. And it is not only a good exercise to have beautiful legs and buttocks , but it also simulates a common gesture in our daily life : sitting down and getting up .

Real case

Recently, a girl who practices the FAST method one day a week told me that she had started an exercise routine at home that the PE teacher had sent her son homework (by the way, great that the teachers encourage movement at home). The routine included squats. This girl’s only experience with squats had been in FAST, so that day was also the first time she had squatted without electrostimulation . His sensation was fantastic, because he felt that this exercise, with his own body weight, without an external load, was hardly effort, felt light and comfortable.

This brief anecdote that I tell you serves as a reference to illustrate that the squat feels and is different with or without electrostimulation. In fact, without using other external stimuli (dumbbells, bars, rubber bands, counter resistance, etc.), the squat without electrostimulation results in a single direction in terms of intra and intermuscular coordination (modifiable with training). However, with electrostimulation we can modify “how we want our muscles to activate” depending on the objectives we have.

There have been innumerable scientific articles that have analyzed the squat, in fact already in 1987 an article was published that analyzed the activity of the trunk musclesby squatting with the pelvis in different positions (retroversion or anteversion) (Delitto, Rose & Apts, 1987). The indications with which the coach gives feedback have emerged from a careful analysis process over decades. Hence, the emphasis is on avoiding valgus, since this increases the activity of the vastus medialis (Felício et al., 2011) with the consequent stress on the patellar tendon, and therefore also on the patella. It is also explained that the coach indicates that you bring your hips back: “previous studies have postulated that changing the projection of your center of gravity behind the feet will decrease the traction of the tibia, therefore it will protect the anterior cruciate ligament” (Nishiwaki, Urabe and Tanaka, 2006).

How squats affect muscles

The muscular activity in the squat not only involves the muscles of the lower limbs , but also the trunk , as we have indicated previously. But the activity of the hamstrings, quads and glutes varies depending on the degrees of the movement. Between 10º and 70º the greatest activity of the hamstrings occurs , and it is from 80º when that of the quadriceps increases, reaching its maximum peak. The buttocks begin their greatest activity at 90º(Schoenfield, 2010). And this activity depends, to a large extent, on the phase you are in: 

Squats, performance increases with electrostimulation

However, this muscle activation can be modified with electrostimulation, for rehabilitation or performance purposes, for example, using methods such as Tonic, Rehability, Strength, Performance or Elite. During the squat, concentric and eccentric contractions occur depending on the phase we are in and the muscle we are referring to. In the descent the quadriceps work eccentrically, and the hamstrings with a concentric contraction, unlike in the ascent.

Knowing this, we can play with these conditions in dynamic squats . For example, we can increase concentric activity on the descent by stimulating only hamstrings., as a strategy within an anterior cruciate ligament injury prevention program. Or we can also increase the eccentric activity of the quadriceps in the descent as integrated work in a rehabilitation after a knee injury. In the ascent phase we can also increase the concentric activity of the quadriceps or the eccentric activity of the hamstrings. These strategies will be focused on the objectives and will be framed within a coherent program. Likewise, for the gluteus, different maneuvers to increase activation can also be integrated depending on the type of contraction.

Use of electrostimulation coactivation

Another alternative using electrostimulation is the use of coactivation, which means that agonist and antagonist muscles contract simultaneously. This technique can be beneficial for sports performance in certain disciplines where maintained positions are required, such as surfing (you can read why in the article ” Wave sports and electrostimulation “).

As you can see, your muscles are not always activated the same with or without certain electrostimulation programs (those that tetanize, that is, that produce an involuntary muscle contraction).

In addition, as indicated before, the squat requires trunk activation to correctly perform the gesture. Therefore, electrostimulation can be a good alternative to increase feedback in the trunk muscles when retroversion, anteversion, hyperlordosis, etc. occurs. This can be done by stimulating or not stimulating some areas, or by increasing their intensity.

These characteristics give coaches a great range of possibilities when training, especially when it comes to readjusting an injury or increasing performance.

The Active Integral EMS in the hands of very good professionals will make your squat one of the best exercises to get the best version of yourself.

References:

• Delitto, Rose and Apts.Electromyographic analysis of two techniques for squat lifting.Phys Ther. 1987 Sep; 67 (9): 1329-34.
• Felício et al. Muscular activity of patella and hip stabilizers of healthy subjects during squat exercises. Rev Bras Fisioter. 2011 May-Jun; 15 (3): 206-11.
• Nishiwaki, Urabe and Tanaka. EMG Analysis of Lower Extremity Muscles in Three Different Squat Exercises. J Jpn Phys Ther Assoc. 2006; 9 (1): 21-6.
• Schoenfeld.Squatting kinematics and kinetics and their application to exercise performance. J Strength Cond Res. 2010 Dec; 24 (12): 3497-506.