Eccentric only squats?

Pain & Rehab Forum [Moderated]
1

Mike,

I saw the videos on instagram of you doing eccentric only squats. Are these part of a rehab protocol? If not, what’s the purpose? I can’t recall seeing others do this.

Apologies if this is off topic.

2

Hey Quark! Thanks for the question. I’ve gotten a few messages about these videos recently.

Anecdotally, this allows the opportunity to get under load that is greater than I am used to walking out and controlling.

In regards to training adaptations:
Hypertrophy - potentially but so far research overall is inconclusive but denotes a few positive studies. See the latest article by Schoenfeld (https://journals.lww.com/nsca-scj/Ab…egy_to.10.aspx).
“The limited body of evidence suggests that with eccentric overload training a potential preferential growth of type IIX muscle fibers and an increased number sarcomeres in series occurs; however, this remains preliminary due to the scarcity of evidence on this topic. There also is evidence that eccentric actions elicit selective distal hypertrophy in the quadriceps that conceivably would result in better symmetrical muscle development under overload conditions. There is no evidence that eccentric overload is an inferior method compared to traditional training. Thus, given the sound rationale for the strategy, it warrants experimentation in hypertrophy-oriented RT program design until research shows otherwise.”

Strength - appears to be valid research for strength improvement. Admittedly, I’ve not read all of these in detail. See:

  1. Chronic Adaptations to Eccentric Training: A Systematic Review - PubMed
    Next two are specific to accentuated eccentric training (eccentric load above concentric 1RM followed by diminished concentric load below 1RM):
  2. Greater Strength Gains after Training with Accentuated Eccentric than Traditional Isoinertial Loads in Already Strength-Trained Men - PubMed
  3. Accentuated Eccentric Loading for Training and Performance: A Review - PubMed
  4. Flywheel - Skeletal muscle functional and structural adaptations after eccentric overload flywheel resistance training: a systematic review and meta-analysis - PubMed

Edit: In my training, these are being used on the last training day of the week as first exercise for an overload that builds to ~122% of concentric 1RM (this is my third week of doing eccentric overload). Afterwards I complete standard squatting (isoinertial) for sets and reps at a % of 1RM.