hamstring stretches

[bingor]

Alright, I want to improve my hamstring flexibility(both dynamic and static), I am aware of what stretches that can help out. My question is when doing something like the seated toe touch or the laid back leg raise towards chest, does the spine remain "neutral" or does the lower back flatten out? The guide on this site shows the lower back flattening out but on others I've read that the back should remain neutral. Thanks in advance.

[Franks]

Very flexible people can keep it straight. Most people curve though.

[Martial Way]

Wouldn't it have something to do with how flexible your back and hamstrings are basically? I'm asking becaue I would think that would determine it.

[bingor]

If I flatten my back I can get my legs slightly past parallel to the waist, once again my goal is to become more flexible, if I keep the back straight I don't even make it close to parallel. So should I try to increase rom in the stretches w/ back flat or straight? I ask not to see which is more productive but what is more likely a safer way to perform these stretches. Anyways thanks to those who already chimed in. Anyone else want to take a crack at these questions?

[Origional]

Keeping the back neutral is best for the spine, so I cannot recommend doing anything that would harm the spine.

If you really want to nail the hamstrings then learn front splits.

[Ashtar]

Rounding the back is something I find happens for 3 reasons:
1. You're focusing too much on getting your hands to your toes instead of stretching your hamstring.
2. You're doing a standing stretch and rounding your back lessens the leveredge disadvantage and your hamstring doesn't have to do as much work.
3. You're doing a sitting stretch and aren't very flexible so rounding your back is really the only way you can actually shift your weight ahead of your hips to help pull your torso/hips down.

Rounding your back briefly is fine, we're supposed to have mobility there for a reason after all. You just shouldn't do it for very long because you risk the back muscles relaxing and just using ligaments to hold you connected which could strain them.

In 'Relax into Stretch' Tsatsouline distinguishes between hamstring and lower back stretching pretty well. When you actually try avoiding the rounding (like by arching) then your realize how little mobility you really have, especially when the knees are kept straight or you dorsiflex the ankle.

[anfeyd]

The hamstrings and lower back are a continuium as Ashtar mentioned (what a surprise, i'm being serious).

The more round the lower back is the less the hamstrings will have to stretch to achieve a desired length. So, if you want a hamstring stretch it is best to keep the lower back locked into neutral. Don't worry about your hands in relation to your toes, just feel the hammys.

[Origional]

The dorsiflexion was quite a good point. I wish I had thought of that!

[Ewasiuk]

Always try to keep your natural arch when stretching the hamstrings and hips. Better stretch and won't make your back sore.

http://img16.imageshack.us/img16/6715/headtoe.jpg

[bingor]

Thanks for the tips guys, neutral spine it is, funny how the front split is mentioned, that is one of my goals for which I'm stretching the hamstrings for. I've read the Relax into Stretch, don't know how I missed that part. For the meantime I'll ignore the whole "reach for your toes" nonsense.

[Ashtar]

One thing I've wondered about is hyperextending the back while doing this...

Anyway, despite all this, in terms of continuum, there are probably fascia you can stretch extra-well if you stretch hamstrings and back at the same time, so it may not be something to rule out.