Keeping Fit: Rethinking the warm-up: The surprising downsides of stretching before exercise

Published 5:00 pm Saturday, March 9, 2024

Stretching before a workout has long been considered a prelude to prime the muscles for activity. However, recent studies and evolving perspectives among fitness experts are challenging this conventional wisdom.

Contrary to the widely held belief that pre-exercise stretching prevents injury and enhances performance, emerging evidence suggests that certain types of stretching might not be as beneficial as once thought, and in some cases could even be counterproductive. This article delves into the nuanced relationship between stretching and exercise, unraveling the reasons why the age-old practice may not be the optimal way to prepare the body for strength and power.

The stretching spectrum

Before we get started, we should clarify the different types of stretching and then bring to light the ones we should probably avoid and the ones we should consider.

Static stretching is what comes to most people’s minds first when they think about stretching. This involves holding a static position for a period of time while allowing the muscles to be lengthened. An example would be a hamstring stretch where you bend over, touch your toes and hold this position for 30-plus seconds.

Next up would be passive stretching, also known as partner stretching. This involves a partner assisting you into a position that would be difficult to reach on your own and then holding you there while you attempt to relax the stretched muscle.

Dynamic stretching involves a controlled movement that gets into a stretched position and then getting back out of it relatively quickly. An example would be a deep body weight squat or a lunge.

Ballistic stretching involves using your body’s momentum to bounce in and out of a stretched position.

PNF, an acronym for proprioceptive neuromuscular facilitation, describes a combination of a passive stretch followed by a contraction of the stretched muscle for five to 10 seconds. After relaxing, your partner will then push you further into the stretch.

Time and place

Now that we have a basic understanding of what each type of stretching is, let’s dive into why we should avoid most of these during our pre-exercise routine. Keep in mind there is a time and place for each, but we are specifically talking about the warm-up before training.

Researchers used to believe that static stretching before training would reduce the risk of a muscular strain. Twenty years ago this was a popular belief but now research shows otherwise. Both the American College of Sports Medicine and the European College of Sports Science have denounced static stretching as a warm-up routine.

Think of your muscle as a spring. If a spring is stretched out and held for a duration of time, much of the elasticity is now gone. The spring will now produce less force. Now that your muscle is all stretched out, your strength and power output will diminish for that training session.

The same goes for PNF stretching and passive stretching as these are basically a different form of static stretch. This can also lead to instability, which in theory could actually lead to injury.

Is there ever a scenario where static stretching forms are valid pre-training? Certainly. If one has a mobility issue that hinders them from getting into the correct position for an exercise, a form of static stretching can be used to help make doing the movement possible with proper form. For example, if your ankle mobility does not allow you to reach a full range of motion squat, performing a calf stretch for 30 seconds could help improve your form. For the reasons already discussed you don’t want to hold the stretch too long. A study released in the Journal of Applied Physiology by Anthony D. Kay explained how stretching for no more than 30 seconds did not significantly reduce force production, but after 45 seconds both strength and power dropped crucially.

Ballistic stretching has its pros but needs to be completed with caution. Recently it has not been recommended by many experts due to the potential risk of injury because of the bouncing motion into a stretch, although certain movements may benefit athletes.

The power of dynamic stretching

Dynamic Stretching can actually improve your performance and is highly recommended pre-training. It involves activating your muscles and moving your joints through the fullest range of motion you can get, which stimulates synovial fluid to wash over the surface of the joints, lubricating them and better preparing you for activity. The muscular movement also slightly increases heart rate and improves blood flow, literally warming up the tissues before the more vigorous workout.

In conclusion, the always evolving health data encourages us to reevaluate our fitness routines no matter what may have been popular years ago. What matters is what is effective. Static stretching can be good, but really should only be applied as a corrective for specific scenarios. Otherwise avoid it pre-exercise and consider more active, dynamic stretching to lubricate joints and warm up your body for the safest and best workouts.

Tucker Gregg is a fitness consultant at the Bradley Wellness Center.