Should you stretch before working out?

It depends on what you need to do the exercise properly, say U of A experts in the second of our two-part series on stretching.

Just as we were getting used to the idea of a dynamic, task-related movement to warm up before we exercise, it appears that stretching of any type will have a similar negative impact on performance.

"I've been around gyms long enough to witness the downfall of static stretching in the early 2000s, the dawn of dynamic stretching a decade later, and now the end of dynamic stretching as well," said Loren Chiu, a University of Alberta biomechanist and strength coach. "Who knows, maybe foam rollers are next."

According to Chiu, neither static nor dynamic stretching has been shown to reduce, or increase, injury risk.

"Attributing any injury or lack thereof to stretching would not only be difficult, but, ethically, almost impossible to study," he said.

Does stretching = warming up?

Chiu suggests we stop looking at stretching like it's a good or bad thing and ask why we're doing it.

"We're looking at the issue of stretching in a binary system, to stretch or not to stretch. But when we look at how the human body does things, you have to look at what the objective of the exercise is and what the body needs," he said.

Chiu added there's a reason it's called warming up: athletes are just trying to increase the temperature of the muscle and tendons, and ensure the limbs have been through a full range of motion before the activity begins.

"Honestly, if you have to walk up or down a set of stairs to get to the gym, your muscles have warmed up. If you're coming in from the cold, you might ride the bike for five minutes, but you don't have to increase your muscle temperature so much that you are sweating. You just need to get them a little warmer than resting temperature."

So how much stretching is necessary when warming up? Chiu said to look no further than the activity itself.

"Take a squat. If you can't get into position to do a squat because your muscles are inflexible, then you should stretch-whatever you need to do the exercise properly. If you can do the exercise properly, then you don't have to stretch."

Stretching during rehab

Chris Zarski, clinical assistant professor in the Faculty of Rehabilitation Medicine at Augustana Campus, contended there is still a place for stretching in the rehabilitation world.

He explained if someone needs to increase the length of a tissue because of an injury or dysfunction-for example, poor hamstring length, which can be a contributing factor to back pain-stretching those muscles helps.

"I often tell patients if the wheel alignment of your car is off, you still can drive, but you start to wear your tires a little bit differently. Static stretching of muscles and other structures can help to improve alignment or activation of muscles."

He explained a patient with a muscle or joint injury might go through a static stretch at first, but over time switch to something that simulates both everyday motion and tasks involved in their activities.

"The idea is to slowly, progressively go through more and more movement, thereby increasing blood flow and warming up the tissues to help healing and regain flexibility," he said.

Zarski added the days where a kids' soccer team would sit around in a circle doing static stretches are probably disappearing, but there will always be a place for having your body ready for any eventuality, especially early in a match.

"Dynamic stretching has been shown to increase blood flow and ensure that the joints have gone through a full range of motion before, for example, a player kicks a soccer ball two minutes into the game for the first time in 48 hours," he said.