Hamstring Weaknesses
Most of the time we do not use our hamstrings very much. The action of these muscles is hip extension and knee flexion. To facilitate significant recruitment of these muscles in normal life you either need to pick-up fairly heavy things (for hip extension) or run forward or climb something (for knee flexion). These are things that we do not do very often in modern live and in all likelihood the most work you do for your hamstrings is getting into and out of the car followed by getting in and out of bed. Compared to the rest of the lower body the hamstrings get almost no work. This leads to the potential for problems.
The two main issues that come out of this are muscle strength imbalances and muscle recruitment deficiencies.
When you have muscles that are imbalanced, the antagonist muscle group is able to contract faster and with more force; in this case the quads for knee extension. If the force is too great the hamstrings can get pulled or torn. The knee and hip joints may also suffer alignment or tracking problems; given that antagonist muscle pairings do offer structural support to the joints making them more stable.
When you have recruitment deficiencies you lack complete control over a muscle. Consciously you may not be able to contract it at will, or with very little force. Unconsciously when you move, the fibers will not contract is efficiently as they could. For example, 50% of the fibers may fire when 35% are needed or 80% fire when 95% of them are needed.
Unless you live with knee or hip pain caused by weak hamstrings you are not likely to notice anything until that rare occasion that you have a very sudden movement that is well outside the realm of normal. For example a car crash were you need to undo your seat belt and crawl you way out of a flipped vehicle or when you suddenly run very fast and your hamstrings are too weak to slow knee extension. New repetitive movements may aggravate patella tracking issues that are caused by hamstring weakness.
Considerations when training hamstrings muscles:
They are primarily fast twitch fibers so they need to be trained quickly on the concentric phase of a movement and the rep ranges should be no more than 10.
You recruit more fibers when you put a muscle on length. A great example of this is allowing your hips to drift back before you start to go down with squatting or when you start to lower the weight with dead lifting. Doing is effectively tilts your hips forward relative to the legs which stretches the hamstrings.
Hamstring muscles adapt very quickly so you need to perform a variety of different movements to train them effectively. Lying, standing, one leg, and Swiss ball curls for knee flexion. Romanian dead lifts, dead lifts, glut/ham raises, reverse hyper extension for hip extension.
Recruit these muscles when you are training your quads by deliberately trying to contract them - by driving the force through the heels with leg press, you transfer some of the effort onto the hamstrings.
If your hamstrings are weak, or if you believe they are, take the time to give them extra attention on leg day. They will catch up quickly if you focus on it and this will improve performance and decrease the risk of injury.
September 27th, 2008 09:37
Please consider the following.
When referencing hamstring strength, a general ratio for musculature balance between quads to hamstrings is a 3:1 ratio. If an individual falls within this, there are considered to have an appropriate balance.
When an individual does heavy lifting they are utilizing more trunk and pelvis flexion and extension rather than hip extension. Hamstrings injuries are primarily from muscular tightness and uncoordinated muscular movement. The main action of biceps femoris, semitendintinosis, and semembranosis, are that of knee flexion and hip extension and also lateral and medial rotation of the tibia although are not a stabilizer for the knee joint. Due to the insertion of the quads group (vastus medialis, rectus femoris, vastus intermedius, and vastus lateralis) on the proximal boarder of the tibia into its tuberosity from the common quads tendon, they play the largest role in stabilization of the knee joint in cooperation with glute max and tensor fascia latae with their insertion into the IT band which primarily aids in steadying the femur on the tibia.
The hamstrings will be pulled or torn when in length especially semembranosis due to some of its slips inserting into the medial tibial margin behind the MCL, hence torn MCL. With hamstring weakness, one will one will be unable to hold in a rotation position. If weak, one will also assume a bow leg position in weight baring stance. In a contracture or tight hamstrings, one will be unable to fully extend at the knee joint and will have a posterior pelvic tilt due to the hamstring origin with the sacrotuberous ligament pulling the pelvis into a posterior position. Hamstring weakness is rather associated with lumbar pain, although with its orientation with the MCL, the knee can be affected.
October 5th, 2008 05:59
Hi Rachel,
Lots of great information in there! Thank you for leaving it!
Pat
February 4th, 2009 14:05
Hey Pat,
Good seeing you at goodlife the other day, just happned to stumble on to your blog.
Of course this post caught my eye.
To begin with, the biggest thing people seem to forget is tha the hamstring is stronger as a hip extensor than a knee flexor. So really leg curls of any variety should be secondary if you decide to use them. Look olympic weight lifters as an example.
I don’t beleive in a 3:1 ratio of quads-to-hams. this type of testing is normally done on a leg flexion extension machine with as I said above doesn’t use the hamstring in its strongest function.
A athlete who has quads stronger than their hamstrings will spend too much time on the ground in the support phase (foot under hip while sprinting). Which can lead to hamstring injuries.
If your athlete feels their quads more than hamstring while sprinting it means that quads strength is greater than the hamstring strength and this is a problem!
Coach Charlie Francis states that cybex testing shows that as the velocity of limb speed increases for both extensors and flexors, the strength ratio changes in favour of the hamstrings.
Flexibility is another major issue, I’ve seen clients aleviead of back pain simply by improving flexibility.
Recovery can be another issue when one is looking to improve hamstring strength.
Next time you are naked in front of the mirror, turn to the side, the hamstring should flow into the glutes, there shouldn’t be a “lip” or indent, not sure how to describe it!
February 4th, 2009 14:52
Hey Paul,
Good seeing you as well and thanks for stopping by and posting a comment! Glad to see you’ve started blogging and are planing on hitting a lean 200 lbs.
I learned the lesson the hard way that hamstrings are hip extensors one day last year when I did 10 sets of 10 with deadlifts supersetted with Romanian deadlifts. The next couple of days were something to forget in terms of lower back and hamstring pain.
I take it from coach Francis’ observations that hamstrings could be viewed as a muscle group that serve an athletic function vs. a practical function - meaning that they are recruited more when one is working at higher intensities. They keep us moving quickly once we’ve hit our top speeds while the quads get us moving.
Thanks for your comments and see you at the gym again soon!
Pat