Adam C. Stewart
Long-term, high-frequency, high-intensity static stretching has recently been found to cause Hypertrophy and strength gain in humans. But how? This review explores exactly that.
Note: This article was the cover of Mass Research Review for October 2023 and is a review of a recent article by Warneke et al. If you want more content like this, subscribe to MASS.
When I saw this review (1), I got excited. I have been interested in hypertrophy induced by stretching since MASS first reported the study by Warneke and his colleagues, which reveals the robust potential of long-term high-frequency static stretching to induce Hypertrophy and strength gain in humans (2). Since then, I have kept a close eye on the work of this research group. I have reviewed important publications such as the comparison of calf stretching with calf resistance training (3) and I have made a video of all the research that this group has published so far. Believe it or not, I even went so far as to get a similar ankle brace used by this group and tried it on myself for 12 weeks (we are currently writing a matter study about it).
As a big Nerd and a competitive bodybuilder (and who has a hard time gaining calves), I find this field fascinating. The big question in my head is, how does this work? More specifically, are the Hypertrophy and strength gains induced by stretching motivated by the same physiological mechanisms as strength training, or are they different? If they differ, can they complement each other? These are open-ended questions, so I was delighted to see Warneke and his colleagues try to address some of them in this work, which helps us to better understand what is happening with stretch-induced hypertrophy and strength gains.
Objective and assumptions
Objective
The purpose of this narrative review was to “discuss the influence of stretching-induced mechanical stress as an underlying mechanism on muscle hypertrophy and strength improvements.”
Hypothesis
The authors did not put forward explicit hypotheses, which is common in narrative reviews.
Methods
Type of evaluation
While narrative reviews are sometimes positioned as an inferior form of evidence compared to systematic reviews and meta-analyses, many narrative reviews simply serve a different purpose. Systematic reviews and meta-analyses are best suited for subjects who have a solid literature that reports outcome data that can be systematically collected and summarized effectively. For this reason, they have specific guidelines for inclusion and exclusion criteria, database search, quality control of studies and, if a meta – analysis is carried out, the statistical Ansatwhile narrative reviews are sometimes positioned as an inferior form of evidence compared to systematic reviews and meta-analyzes, of Systematic reviews and meta-analyzes are best suited for subjects who have a solid literature that reports data on the results that can be systematically collected and summarized effectively. For this reason, they have specific guidelines for inclusion and exclusion criteria, database research, quality control of studies and, if a meta – analysis is carried out, The statistical approach. For example, a systematic review on HMB (with or without meta-analysis) would discuss all relevant studies examining various outcomes of interest in different populations over the years. It would probably recognize the proposed mechanisms that lead to these results, but it should also include a qualitative or quantitative comparison of specific results in response to HMB consumption with Placebos or controls.
Sometimes you come across a narrative review that is a systematic review or meta-Anal Rightly, you come across a narrative review that could have been a systematic review or meta-analysis, but authors more often write narrative reviews to discuss a possible mechanism, cover a broad or multifaceted topic, clarify the methodology or all of the above. This review is an example of this.
Review the strategy
When writing a narrative journal, researchers have great latitude to define their research strategy and their inclusion criteria. The authors described their approach as follows:
“Since it is a narrative review”Since it is a narrative review, the authors have tried to reflect the essential state of the literature through an extensive study research. However, since there are a large number of studies, in particular on the effects of stretching on flexibility in humans and on Hypertrophy in animals, it was necessary to concentrate the literature review, which may have led to the absence of some studies in the review article. To analyze the studies that answer our research question, we first reviewed the current systematic review articles on the subject(4, 5, 6, 7, 8). Related articles and reference lists were then examined to find articles excluded from the aforementioned systematic reviews. In addition, this review took into account only those studies that.
