RF is extremely important in sprinting, jumping and weightlifting. A bi-articular muscle, it holds isometrically to permit transmission of force from the hip extensors. What many don’t realise is that a knee extension exercise such as squats induces only moderate activation in the RF. What is also interesting is the significant positive effect that electrostimulation of RF has on squat !RM.
I contend we should dedicate special attention to the RF in a similar way that we do for the hamstrings. THis means devising appropriate hip flexion exercises. This has obvious difficulties since gravity is acting downwards!! Perhaps ‘bowing’ like movements using cables is the answer?
another problem when devising and exercise; when attempting to fix the weight somehow at the feet there is a problem of the isometric contractions the smaller muscles of the lower leg might have to make just to keep the weight secure, therefore tiring out before the set is completed.
Originally posted by David W
How do you increase the resistance?
I have thought about that too. Holding a weight between your legs is too tedious. Balancing a barbell on top of your toes does not work, as at the end of the concentric the weight comes loose.
I have thought about making a “special” device that would hold a barbell under the soles of your feet. I will try and describe what I am thinking of. If you took a strand of thick metal (about 30cm long and 1cm thick) and curled each end into hooks and then bent the centre so that the hooked ends were opposite each other. The curved centre would act as a bridge across the top of the foot while the hooked ends would hold a barbell under the soles of the feet. One would be needed for both foot to hold a barbell. What do you think?
Originally posted by JimboUKdec
another problem when devising and exercise; when attempting to fix the weight somehow at the feet there is a problem of the isometric contractions the smaller muscles of the lower leg might have to make just to keep the weight secure, therefore tiring out before the set is completed.
This would be just the same a grip problem when holding a barbell in your hands. Eventually your grip becomes strong enough to hold most any weight. Why should it be any different for your feet/ankles?
chris30: the RF crosses both the knee and the hip, so unlike the other quad muscles it not only extends the knee, but also flexes the hip.
David W:
Dave Tate from Westside in his seminar video says he was stuck at about 830 on his squat, then increased his hip flexion (abs and hip flexors) strength with Ab pulldowns (standing) and his squat went up over 900. He felt that the missing link at that time for him was his core strength.
Check out this article from him posted at muscle monthly.
If one doesn´t have a lat pulldown machine, or anything fancy for hip flexors, you could anchor the feet and do straight legged or bent legged situps with a weight hold on the chest or behind the head. But I would supplement this with lower ab isolation work and hip flexor (RF and ilio psoas) stretching so that the hip flexors don´t get tight and that you can keep the pelvis in a neutral position with the abs (i.e. pelvis not tilted forward due to strong but short hip flexors).
This might not be a great way to do leg raises with weight, but i use some spare thick climber’s webbing and tie it around my ankles and attach the webbing to the weight plates. I also do them stiff legged. This way i can hit the hips better with less weight. Would doing stiff-legged leg raise still get the Rectus Femorus (Spelling)?
I’ve been doing explosive straight leg pikes for quite some time, combined with bent legs ones as well. Really getting the legs behind the body at the bottom and power all the way up till my legs are aimed skyward
guess I was doing something right for once without knowing it
Off course there are machines that do work this movement at my gym…
you know ankle weights or gravity boots are handy here too …
I could possibly add a more difficult variation. Sit in the leg extension machine, and make sure to maintain a straight back. Flex the hip and raise your knee 2-3 inches off of the leg support on the seat, and then extend the knee (all while keeping your back straight). This exercise will destroy your rectus femoris.
I can hook my feet under top of my cabinet which is built in to the wall so it isn’t moving, and stick my butt on the bench and my back is not supported by anything. Hold weight on my chest and go up and down.
One other version of leg extensions- Perform them while lying back on a flat bench, this puts the RF in a prestretched position for higher activation. I also believe sissy squats activate it quite well?
