[Music] in my last science explain video i covered the most scientific way to train the quads of course i think any complete lower body regime must balance its quad work with roughly equal hamstring work strengthening the hamstrings is important for injury prevention and athletic performance so in this case it's not just about aesthetics and as always before we can understand how to train the hamstrings most effectively we need to cover their basic anatomy first for practical purposes the hamstrings can be split into a lateral or outside aspect and a medial or inside aspect and then
a proximal or upper and distal or lower region the hamstrings are made up of four distinct muscles starting most medially is the semi-membranosis with the semitendinosus in the middle and the biceps femoris sitting most laterally which is itself split into a short head and a long head which have slightly different functions so the semimembranosus and tendinosis both originate at the pelvis and insert on the tibia which is the big shin bone the biceps femoris long head also originates at the pelvis and also inserts below the knee but on the smaller fibula bone just lateral to
the tibia these three muscles are biarticular muscles meaning they cross both the hip joint and the knee joint and as such can perform hip extension like in a deadlift and knee flexion like in a leg curl the biceps femoris short head on the other hand only crosses the knee joint not the hip joint and as such can only function to flex the knee having no action at the hip at all okay so based on this anatomy with the hamstrings we have four muscles that can flex the knee and three muscles that can extend the hip
so to train the hamstrings most effectively for development we need to be using exercises that train hip extension exercises that train knee flexion and perhaps exercises that hit both at once in my quad science explained video i made a big deal out of the squat as arguably the best quad builder and since the squat trains hip extension it stands to reason that it'd also be a good hamstring builder right well actually the squat is a really bad hamstring exercise when you think about it biomechanically it makes sense because with the squat you're training hip extension
and knee extension simultaneously so what this means is that the hamstrings are shortening proximally as the hips extend but lengthening distally as the knees extend so the hamstrings are being stretched at one end and slackened at the other so the net effect is that the muscle length is more or less constant throughout the squat range of motion leading to very little tensile stimulus for growth and this idea is supported by many emg studies including a 2009 paper from ebenetal which showed the squat to be by far the worst exercise out of the six movements tested
for activating the hamstrings now the deadlift is pretty similar to the squat and that it also trains simultaneous knee and hip extension however since the hips are much higher at the start of the deadlift the knees are not as flexed and so the hamstrings are in a better position to contract and contribute to the hip extension portion of the movement and again this plays out in emg data where we see that according to a 2002 study from escamilla and colleagues both conventional and sumo deadlifts lead to quite high levels of hamstrings activation and if you
remember this study from the quad science explained video again while the squat sucked the deadlift was number one for hamstring's activation and while the stiff-legged or romanian deadlift variations are popular movements for isolating the hamstrings research hasn't shown much activation difference between these movements and the conventional deadlift but with that said i still prefer using a straight leg for hamstrings emphasis because it places a greater degree of stretch on the hamstrings which may be important for anabolic signaling other exercises that train pure hip extension like the lower back extension and reverse hyper are also quite
effective at hitting the hamstrings and can be included in a solid hamstrings focus program so i've been talking a lot about hip extension based exercises but what about knee flexion well for the most part any exercise i can think of that involves flexing the knee is going to have pretty high hamstrings involvement i'm not going to make a big deal out of nitpicking the differences between these however one 2012 study looked at emg activation for 14 different exercises and found the slide leg exercise to come out on top one thing i really like about this
exercise is that the hips are being actively extended while you curl the legs in and while it's a bit awkward to do as they did in the study i think a more practical alternative is brett contreras gliding leg curl where you fully extend the hips and curl your body in toward a high plyo box while hanging from a barbell another variation on this i found to be helpful can be done on a seated rowing machine where you put your feet on the seat upper back on the floor and curl the seat in toward your body
and i think the reason why these exercises are so good for the hamstrings is that they have to work to keep the hips extended isometrically and to concentrically flex the knees at the same time the glute ham raise is another exercise that hits both functions at once so all of these are great i don't personally have a strong preference for either the lying or seated machine leg curl and since emg activation is similar between the two i think you should use whatever one you feel working your hamstrings the best or use both periodically for variety
what is perhaps more interesting is that similar to the quads with the leg extensions how you position your feet during leg curls can affect which region of the hamstrings is targeted data from linen costigan showed that external rotation or pointing your toes out activated the lateral or outer hamstrings more while pointing your toes in activated the medial hamstrings more one way i like to remember this is to point your toes in the direction of the hamstrings region you're trying to activate a 2015 paper from schoenfeld and others showed regional differences in activation as well the
lying leg curl was better than the stiff leg deadlift at activating the distal or lower portion of the hamstrings while there was no significant difference between the two exercises for proximal or upper hamstring activation this implies that in order to fully activate the hamstrings across their entire length it isn't enough to only deadlift an exercise that isolates knee flexion is important to include as well and also recall that the biceps femoris short head doesn't even cross the hip so if you only do hip extension based exercises you won't be targeting this muscle at all and
contrary to very popular belief the hamstrings are not fast twitch dominant new data with improved methodology has revealed the hamstrings to be a pretty even mix of type 1 and type 2 fibers implying that both high and low reps should be used i prefer to use primarily lower reps and relatively heavier weight when doing heavy hip extension based movements like a stiff leg deadlift however going too heavy is a very common mistake causing the lower back and glutes to take over and i think establishing a good mind muscle connection and feeling a strong stretch under
complete control is essential for optimizing this movement high rep deadlifts are also fine but i prefer to use the dumbbell variation for more of the pump work since their capacity for loading is lower anyway for lead curls again high and low reps can be used one recommended program might look something like this you train hamstrings twice per week probably on lower body days and unlike day one you do a heavy stiff leg deadlift for four to eight reps and a light leg curl based movement for eight to twenty reps on leg day two two to
three days later you do a heavy leg curl based movement for four to eight reps and a light hip extension based movement for eight to twenty reps and on either of these days you can add in one more supplemental exercise especially if your hamstrings are lagging however be wary not to exceed 20 sets for the hamstrings per week as similar to the quads and according to dr mike izertel this is when most trainees start running into recovery issues so try not to be like the majority of gym goers and neglect the muscles you can't see
when facing the mirror the hamstrings are important to develop for injury prevention athletic performance and to give a much more complete muscular appearance from the side and the back and with these new scientific principles in mind i hope you make the most hamstring gains you possibly can all right what is going on everyone uh first of all i just want to say thank you for watching the video and i also want to quickly thank skillshare for sponsoring this video in case any of you guys aren't aware skillshare is an online learning community designed to help
creators take their passion and turn it into a full-time job it's crazy for me to think that just simply creating these videos has turned from a hobby to a full-time career for me now at this point and i think that a big part of making that step was just improving and increasing my attention to detail and especially when it comes to the editing and the production value of this information and i think that skillshare really is the perfect resource for doing this skillshare gives you access to more than 17 000 professional classes things to do
with photography videography business productivity web design anything really that's going to help you take your content to the next level so i'd like to recommend two courses to you guys the first is visual storytelling with final cut pro 10 second edition which has 37 classes explaining all the ins and outs of my preferred editing software which is final cut pro and the other is fundamentals of dslr photography which is another thing that i think is really important for increasing the production value on youtube instagram or anywhere else where you're sharing photos and video so a
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make sure that you're one of the first 700 uh thanks again to skillshare for sponsoring the video thank you guys so much for watching i've got a back training science video on the way i'm just putting together all of my research for that video so you can be on the lookout for that one probably next weekend and if you guys can't tell we are back in our canadian home right now and it is freezing here compared to florida right now but we're gonna be here until christmas and then for the new year and then we're
heading to the la fit expo and then back to florida for a bit after that um so i think i'm gonna do a couple vlogs while still here in kelowna so maybe tomorrow or the next day i'll film for that so i've got lots of content coming be on the lookout don't forget to hit the thumbs up button and like this video and subscribe if you're new and i will see you guys next time
