This blog is made from the high amount of people reacting to this post we had talking about nordics and razor curls.
As you see in that video, the athlete does not have the strength to perform the razor curl without assistance from his hands. However, earlier in the day he was able to sprint max velocity and hit over 20mph on a Dashr timing system. Which made me think, if he can run that fast but cannot do a razor curl - does he need to be able to do a razor curl in order to stay healthy while sprinting?
We already know that he does not need to be able to perform a razor curl in order to run fast. High school kid running over 20mph on a Dashr with 20 yard build up is fast. But how long can he do that before he hurts his hamstring? Idk. No one does. If anyone says they do know, they are either lying or full of it. How could they know? What is the exact number of reps or distance run before there is an injury? No one knows.
What we do know is weak things eventually do break and athletes need to train in the weight room to build up their strength. Sprinting and sport alone does not place enough requisite stimulus for strength or hypertrophy in athletes. This is where the weight room, although general, comes into play and helps.
Look At Research on Hamstrings
The research is really clear that using nordics, leg curls (prone and spine), or SL iso hold on GHR help improve hamstring strength (1, 2, 3, 4, 5). The question most of us S&C coaches ask ourselves is what is the best? We always want to know what is the best don't we? The hard part is it all depends. Leg curls are knee dominant while iso holds are more hip dominant. Also, one is bilateral, the other is unilateral. This is why I think you need to do both. You can't say just do this and it will make your hamstring injuries go away.
Image from Macdonald et al (2019)
The only thing that can is train. Just train (properly) and hamstring injuries can go away. Part of proper training is doing hip dominant and knee dominant posterior chain exercises. Both need to be done unilaterally and bilaterally. Both need to be done for all contraction types: eccentric, isometric, concentric, dynamic reversal, 1.5 rep, etc... This also needs to be done from simple to complex with exercise secretion, muscle contraction, and load.
Image from Çilli et al (2021).
For example, if you took a completely novice athlete that has never trained before, put them on a GHR and said do 3x8 to strengthen your hamstrings, perhaps you are misguided. Chances are this athlete cannot do that, and would benefit from a physioball or TRX leg curl. Starting here will allow the athlete to keep his or her hips in neutral alignment on the exercise while strengthening the posterior chain.
Image from Delextrat et al (2019).
What Exercises and Tempo to Use
As I mentioned above we need to ensure our athletes programs are robust in the weight room and on the field. We cannot say one exercise will stop hamstring injury. If we had to pick one it would be sprinting. Doses of the thing we are trying to avoid being hurt from will help build robustness in that skill. This is the S.A.I.D principle - specific adaptation to imposed demands. Here is an example of S.A.I.D
"The results of the within-group analysis are reported inTable 2. The single-leg Roman chair hold group showed a very likely moderate magni-tude improvement on SLHB performance for both legs. By Contrast, the Nordic curl group showed a likely trivial change in SLHB performance for the non injured leg and an unclear,but possible (80% chance) triv-ial change for the previously injured leg" (5)
This makes sense because the SL roman chair hold is more of a hip dominant movement (so is hip bridge). Therefore it makes sense to see this result.
However, sprinting alone isn't enough to build strength and size. So we lift. And when we lift we need to hit:
Posterior chain knee dominant bilateral: Example - Nordic
Posterior chain knee dominant unilateral: Example - SL leg curl
Posterior chain hip dominant bilateral: Example - RDL
Posterior chain hip dominant unilateral: Example - SL hip bridge
Within this you can program slow, iso, and dynamic contraction. I would recommend using isometric movements first to build strength in the end range. Keep the reps low to accomodate for the time holding.
Example:
BB RDL
Week 1 - 4x5 with 3 sec iso at bottom - 50/60/70/70 for percents on the load.
Week 2 - 4x5 with 3 sec iso at bottom - 55/65/75/75 for percents on the load.
Week 3 - 4x5 with 4 sec iso at bottom - 55/65/75/75 for percents on the load.
From here you can switch the contraction type, or reduce the reps while increasing the load. Use your head on what works best for your team and all the logistics that go with it.
Secret Weapon Exercise for Posterior Chain Development
Since we know we need to train the posterior chain to reduce the liklihood of injuries and potential severity of these injuries, and since I just showed you all the categories to train the posterior chain - here is a way to target the hamstrings (BF, ST, SM) while keeping the torso in neutral alignment, and can do it double or single leg.
With this piece of equipment you no longer have to worry about your athletes performing a nordic flop (that is where they hold the nordic at the top, fight for 2 seconds, and then flop on the ground). Now they can train their PC in knee flexion through the full ROM cuz of the device set up. This is perfect for coaches with heavier athletes who struggle with partner nordics. It is also ideal for coaches with generally weak athletes, or any athlete returning from injury. Now you have an EXACT weight of assistance and settings that you can track and collaborate with ATC.
I personally used this device at Power Lift HQ in Jefferson, IA and LOVED how it felt on my hamstrings. This also feels great on your knees as I am not a huge fan my patella being shoved into the ground with partner nordics. I am not ignorant enough to think this one exercise will stop hamstring injuries. I do know this exercise performed on this device got my hamstrings, groin, and calves fired up WAY more than a partner or band assisted nordic. When I am in the weight room and want to develop strength of my muscles I want them to be a strong as possible. That is what this device does.
So I highly recommend you look into this product and add it to your arsenal of equipment in your facility. You can get more info on the device by clicking here and by talking to one of the reps at Power Lift. You'll like the way it feels - I guarantee it.
PS - Don't just take my word for it. Assistant AD for Strength & Conditioning / Assistant Head Coach Football Bret Huth loves this device too. Check out the protocol he posted on social media. Give this one a shot!
References:
(1) Delextrat et al (2019). Changes in Torque-Angle Profiles of the Hamstrings and Hamstrings-to-Quadriceps Ratio After Two Hamstring Strengthening Exercise Interventions in Female Hockey Players. Journal of Strength and Conditioning Research 34(2)/396–405
(2) Monajati et al (2021). Injury Prevention Programs Based on Flywheel vs. Body Weight Resistance in Recreational Athletes. Journal of Strength and Conditioning Research 35():p S188-S196, February 2021. | DOI: 10.1519/JSC.0000000000002878
(3) Çilli et al (2021). Electromyographic responses to Nordic curl and prone leg curl exercises in football players. November 2021 Physical Education of Students 25(5):288-298
DOI: 10.15561/20755279.2021.0505
(4) Islam et al (2024). Nordic Hamstring Curls are a Remedy for Hamstring Muscle Injury: A Narrative Review. International Journal of Human Movement and Sports Sciences 12(4): 692-698, 2024 DOI: 10.13189/saj.2024.120411
(5) Macdonald et al (2019). The Single-Leg Roman Chair Hold is More Effective than the Nordic Hamstring Curl in Improving Hamstring Strength-Endurance in Gaelic Footballers with Previous Hamstring Injury. Journal of Strength and Conditioning Research. 2018 National Strength and Conditioning Association 33(12)/3302–3308. DOI: 10.1519/JSC.0000000000002526
