Single worst exercise?

[shouldbworking]

996 sps said:

swerni said:

leg extensions.

Ask any competent physio and they will say avoid like the plague

Yep they do as they are an open chain exercise and expose the ligaments to shear forces, again if the ligaments attached have no form of graded strains/ruptures the you could argue that if quads and hamstrings are strong enough then carry on. Not always a heavy weight though but sports specific a kicking sport has to expose knee exten to a form of open chain exercise.

Can someone explain this one a little more to me? these form a part of our karate warm up routines (1 set of 20 reps) and I'd like to understand the risk a little more.

Thanks

[996 sps]

They say that when the foot is not in contact with the floor and you place a strain at the end of the lever arm (i.e. the foot with the contact of the leg ext machine) a shear force is placed on the ligaments from the tib and fib being moved under load, if you google words to the effect of "open chain exercises vs close chain exercises" it should bring plenty up.

They also say that close chain exercises i.e. the squat is more functional than open chain type exercises.

[RemainAllHoof]

Interesting. So, a snap front kick and a backfist or hammer fist are forms of open chain exercises especially if contact is made with a heavy object (bag/body)?

[996 sps]

996 sps said:

swerni said:

leg extensions.

Ask any competent physio and they will say avoid like the plague

Yep they do as they are an open chain exercise and expose the ligaments to shear forces, again if the ligaments attached have no form of graded strains/ruptures the you could argue that if quads and hamstrings are strong enough then carry on. Not always a heavy weight though but sports specific a kicking sport has to expose knee exten to a form of open chain exercise.

Already mentioned that here mate, different shear forces to that of heavy weight over an amount of sets to that of sports specific kicking.

[RemainAllHoof]

Sure, just wanted to clarify.

[996 sps]

RemainAllHoof said:

Sure, just wanted to clarify.

I would defo read the research though mate as everything changes so quick and can only mention what I was taught a few years ago.

[RemainAllHoof]

Fair enough; there were quite a few interesting sites.

[Lost_BMW]

Strange thing is though that I've seen several different clips on TV of medics using leg extensions when rehabilitating athletes or old folk after knee surgery/ leg injuries?

[swansea v6]

Lost_BMW said:

Strange thing is though that I've seen several different clips on TV of medics using leg extensions when rehabilitating athletes or old folk after knee surgery/ leg injuries?

Its usually a case of weighing up benefit of exercise V's any negatives. With the leg extension as long as the weight is not too heavy, then it used to 'isolate' the quads. Although a squat is a much better exercise, there are scenarios where it would not be advisable to train a client using a squat, so you look for alternatives.