How Long do you Need to Stretch For?

I think the duration of the 'stretch' is very important. Keep in mind that what we're talking about is giving muscles 'confidence' that it is safe to loosen off. It's not stretching per se, but creating the conditions for the muscle to loosen off that we need to focus on.

I'd say it takes at least a minute for a muscle to get the message it is safe to loosen up, maybe even longer. With lower back pain, you'd want to allocate 20 minutes for each of static back, supine groin stretch and hip crossover. Most people only stretch for 20 seconds and wonder why they never get better.

If you're planning on loosening a muscle, take10 or 20 long, slow breaths and with every breath you breathe out increase the 'stretch', even by the smallest amount.

For instance, with a conventional hamstring 'stretch' with one leg on a bar, with every breath you breathe out, take your navel a little closer to your thigh. With 20 deep breaths you'll make a lot of progress. Tust give the muscle time and respect.

I haven't expressed this in scientific terms but you'll get the message.