Passive Stretching Makes Experienced Lifters Weaker
One important question to consider when reading studies involving responses to exercise is the extent to which they affect people of different fitness levels. Many more studies are done on novice lifters than advanced athletes. The results of these studies could be said to apply only to novices, who respond differently to training. Every experienced trainee was a novice at one point and knows that the response to training is different.
In a recent article I discussed a topic that has been getting a lot of attention lately - passive stretching before physical activity. The article summarized a study that found passive stretching as a warm up reduces your strength. However, since these things change with experience, it’s important to distinguish between advanced lifters and novices. Perhaps, as with many other training variables, the negative impact of static stretching is lessened with time and experience. A study this month in the Journal of Strength and Conditioning investigated this topic.
In case you’re not familiar with the term, passive static stretching is the kind you most commonly think of when you hear the word “stretching.” It's basically what you're doing when you move into a stretch, relax, and let gravity do its thing for a bit. This is very different from active forms of stretching, in which you engage musculature to assist in the stretch, and dynamic forms of stretching, in which you do not stop movement in the stretch.
In the study, researchers compared untrained participants to those with a fair bit of experience. The advanced group had performed resistance training for a minimum of six days a week for six months. They were well beyond their beginner’s gains and knew the exercises involved. The researchers wanted to find out if there were any differences between the two groups and, further, if the changes in strength held true for all of the body’s musculature.
The results were almost universal. Static stretching makes you weaker when performed before weightlifting. Whether we're talking about the upper body or lower body, novice athletes or experienced lifters, the reduction in strength persists pretty evenly across the board. The only significant difference was in the bicep curl. In this case, both groups still got weaker overall, but the veteran athletes didn't experience quite as much loss in strength as the newbies.
Now, it’s important to note that static stretching isn’t bad, per se. However, this study suggests that it does limit your maximum strength when performed prior to strength training. The effect may last for a while, but I think it’s okay to do static stretching before bed at night or something similar, as long as you give static stretching its own time.
While it’s great to further clarify this topic, I do love static stretching. I’d really like to see a study that asked whether strength is also reduced in people who have long-term experience with static stretching and weightlifting. I suspect if you were used to static stretching before heavy lifting, the reduction in strength wouldn’t be so dramatic. Until that study comes out, it’s best to just avoid passive static stretching right before you lift weights.
1. AJ Serra, et. al., “Experience in resistance training does not prevent reduction in muscle strength evoked by passive static stretching,” Journal of Strength and Conditioning Research, 27(8), 2013.
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