Stretching is everywhere. From PE classes all the way to professional sports, you’ll often see some form of stretching. But research nowadays has shown that certain types of stretching may not be as good as they were portrayed to be, especially for performance related outcomes. But what about strength? Is stretching useful for muscle strength or a potential gains killer?
What did they test? The authors examined the current literature to better understand the effects of stretching on muscle strength.
What did they find? Stretching does not seem to have a meaningful effect on muscle strength, although it may lead to slight decreases if performed over time (>12 weeks).
What does it mean for you? If stretching is something you really enjoy, you can do so safely without worrying about your strength gains, although it may be ideal to do it separately from your lifting sessions.
What’s the Problem?
Static stretching, as previously mentioned in the January 2023 issue of REPS, has gone from being “THE” warm-up tool and (wrongly) injury prevention method, to being the “worst possible thing for your performance” and somewhat replaced by dynamic stretching due to having less detrimental effects of performance. Some of those studies showed that static stretching may negatively affect strength performance, which had a lot of people in the evidence based fitness world stray away from any sort of pre workout stretching. Recent studies have shown that the type of stretching you do along with its duration and intensity may be the most important variables in determining whether stretching will boost performance, including strength, with dynamic stretching showing positive effects on a few performance variables and longer duration static stretching showing detrimental effects of strength (although of a small magnitude).
The one issue that exists with the current stretching literature is that much of the focus is placed on the effects of acute stretching on performance rather than chronic stretching, with evidence on the latter being rather limited. Previous research has highlighted the need for more evidence on the effects of chronic stretching, especially in the context of muscle strength.
Stretching is something that a lot of active individuals enjoy performing as it allows them to feel more mobile, warmed-up and even relaxed, so understanding whether it can negatively affect strength in the long term is important as acute effects don’t always tell the whole story. For example we know that caffeine can acutely increase blood pressure but those effects diminish over time and won’t necessarily lead to chronic blood pressure. Similarly, certain forms of stretching may acutely result in a small negative effect on strength but that may not be the case in the long term. Since the last systematic review was published on the topic, there have been plenty of new studies that have come out investigating the long term effects of stretching with or without resistance training on muscle strength. Thus, this review published in December 2022 by Ewan et al may be able to shine some light on whether stretching is a good or bad idea before a lifting session.
Purpose & Hypothesis
The authors did not formally state a hypothesis but their aim was to review all the studies on the effects of long term stretching on strength that came out in the last 5 or so years (including the limited evidence that existed before).