Ever since I started training clients in a big box gym a couple of years back I've had every person doing some sort of dynamic warm-up of the type talked about in the NYT article. I find it amusing that we still get funny looks from many gym members who must wonder what the hell that person is doing crawling around on the floor. But then again most large gyms are not exactly a bastion of fitness knowledge.
The topic of dynamic warm-ups and mobility work has been discussed for years in the strength and conditioning community. Studies showing static stretching actually makes you weaker date back a number of years, so it's great to see this information finally filtering down into popular media.
The old presumption that holding a stretch for 20 to 30 seconds — known as static stretching — primes muscles for a workout is dead wrong. It actually weakens them. In a recent study conducted at the University of Nevada, Las Vegas, athletes generated less force from their leg muscles after static stretching than they did after not stretching at all. Other studies have found that this stretching decreases muscle strength by as much as 30 percent. Also, stretching one leg’s muscles can reduce strength in the other leg as well, probably because the central nervous system rebels against the movements.
The reason it temporarily weakens muscles is that static stretching gradually increases one's flexibility by inducing micro-tears in the muscle. It only makes sense that these micro-tears, though good for long term flexibility, take time to rebuild, right?
For the record I wish I would have known this years ago before screwing up my knees doing idiotic stretching before martial arts practice.
To be clear I do advocate static stretching for just about everyone, but do it any time OTHER than immediately before exercising.
As for other functions a dynamic warm-up serves:
THE RIGHT WARM-UP should do two things: loosen muscles and tendons to increase the range of motion of various joints, and literally warm up the body. When you’re at rest, there’s less blood flow to muscles and tendons, and they stiffen. “You need to make tissues and tendons compliant before beginning exercise,” Knudson says.
A well-designed warm-up starts by increasing body heat and blood flow. Warm muscles and dilated blood vessels pull oxygen from the bloodstream more efficiently and use stored muscle fuel more effectively. They also withstand loads better.
One quibble I have with the NYT article is the inclusion of scorpions. Most people do not need more low back flexibility, as the lumbar spine is meant to stabilize, not rotate beyond a few degrees. As for the hip flexors and glutes, there are better movements that address those areas.
For more info on back issues it doesn't get any better than Dr. Stuart McGill.
In addition to dynamic warm-ups almost everyone needs mobility (increasing joint range of motion) and soft tissue work (breaking up scar tissue and increasing muscle pliability).
To break it down, you will reach your goals quicker and stay healthier by including dynamic warm-ups into your training.