Recurring hamstrings tears.... or are they cramps?

For the last few years, I've averaged one or two hamstring pulls/tears each field hockey season, and I've always put it down to overtraining / tight hamstrings brought to a head by sprinting or over-stretching.

However, a team-mate has recently said that it could just be cramps?

Co-incidentally, since he's mentioned this my left hamstring (usually the non-tearing hamstring), has been quite 'twitchy' and almost on the point of cramp in a few totally innocuous situations (moving a bin, leaning over etc.).

How do I distinguish between a cramp and a minor pull in the hamstring, and if it is cramps, why might I be suffering them so often?

Sounds more like a neural, low back issue. There is not reason you would tear a muscle unless you force it to contract excessively or perhaps over stretch it (maybe ballistically). Moving a bin is likely to be some form of connective tissue/referral issue. Twitchy muscles would also back that up.

Thanks for the info. It's interesting you should say low back issue, as it has been a little tight / sore of late as a result of some fairly heavy squatting. IMHO, there's no weakness there as I'm smashing PBs, but I guess this could cause problems that manifest at other times? If so, is it just a case of taking it easy for a bit / rest / stretching etc., or is there something more specific I should be doing?

As for the second point on connective tissue / referral, I'm not quite sure what you mean by that. How would I go about establishing if this is the case or even treating / preventing it?

I'm down with PBob on this one, The fact your feeling twitchy doing things like "moving a bin, leaning over etc" is indicative of low back because you are flexing the lower spine. Not to go into much detail but if your getting problems when you flex the lower spine the logical thing is to do back extensions as per a Mckenzie based approach (The McKenzie Institute - Welcome to the McKenzie Institute International). Again keeping it basic - an exercise that you can try is a backward bend much like the Cobra position you see in Yoga, the point is to be repetitive with it. Do it like a pressup but keep your hips on the ground. Do about 10 5-6 times a day.
This is a simple exercise you can try that I'm confident you will be able to manage with little risk (based on the small amount of information you'v given about some of your workout activities).
What I'v described is both treatment and diagnostic - if it doesn't make a difference then it's likely that the problem is not coming from the disc's of the back and I would suggest you visit someone to get a more thorough assessment. It could be a neural tension issue which can be assessed and then the correct exercises given for example.

All the Best,
Pudding

Well I've started the cobra press-up type exercises, so I'll see how they work out for me. Quick question on technique though ; how high should I press? If I straighten my arms, but leave my shoulders pushed back, my hips just about stay on the floor. Should I push through until my shoulders are fully forward as this would leave my hips hanging (albeit with a stretched back)?

As for the back extensions, what sort of regiment should I be doing for them, i.e. weight/reps/sets/range of motion etc?

Just in case it's relevant, I've included my current training below:

Monday - Gym (all exercises are three work sets of five reps):
Squat - 175kg
Calf raise - 140kg (three sets of twelve)
Dips - Bodyweight + 20kg
Standing barbell shoulder press - 67.5kg
Pec dec - 125lbs
Abs - 20kg incline ab curls or leg raises (three sets of eight)

Tuesday - Hockey Training (90 minutes, mix of sprints, steady states and standing about)

Wednesday - Gym
Chins - Bodyweight + 10kg
Low rows - 87.5kg
Power shrugs - 130kg
Bicep curl - 47.5kg
Rotator cuff work (a mix of exercises and weights)
Side bends - 45kg (three sets of eight)

Thursday - Hockey Training

Saturday - Hockey Match