🚨🚨We finally managed to push out our multifactorial & individualized hamstring risk reduction intervention in professional soccer. @PascalEdouard42 @jb_morin @zentrumsport et al Here is a 🧵 of the results and some interpretation (some extra figures also).

Biomechanists, would there technically be any difference between the nordic at 90 degrees, and seated knee flexions? With my logic the stimuli should be the highly similar if done eccentrically?

When reading resisted sprint papers that have compared phases (including our teams earlier work), be aware of phase approach comparisons (e.g. comparing 20-25 m interval etc). It seems more accurate to compare the step at a similar velocity between conditions to get an idea of

EMG hamstring question. Has someone here measured tantrums and compared it to the EMG during sprinting? I did it today and for the lateral hamstrings im getting average readings of nearly 150% compared to sprinting! Didnt expect that.. For medial hamstrings its closer to 60%. Did

🚨NEW PAPER🚨 Sprint acceleration mechanics in Division 1 college American Football players🏈 Initial sprint kinetics, kinematics and correlation with performance metrics by position/line Well done @CoachJosse👏 @KenClarkSpeed &al in @JSportsSci more soon https://t.co/Lvp5FSbTsz

We need more performance intervention studies for comparing specificity of transfer on limb velocities vs intent. If you look at isokinetic studies comparing concentric vs eccentric contractions at different velocities, movement velocity does seem specific (fast eccentrics have

Another very nice hammy study for today by @KerinPerform

🔥Very interesting new hammy study by ⁦@StephLaz_⁩ et al in #SJMSS “Differences in Hamstring Muscle-Tendon Unit Geometry and Function Between Elite Sprint and Jump Athletes and Recreationally Active Controls”.

What a weekend of learning and sharing at the @SportsmithHQ Strength & Power conference. Too much to get thru but briefly in my session we looked at - role of and methods to ⬆️ Motor Unit Recruitment

Effects of Fatigue Induced by Sprinting on Biomechanics and Potential Hamstring Injury Risk. 🔗 https://t.co/3ODArMufZj Figure 9| Hamstring related performance changes post repeated sprints (A) and individual pelvic movement changes (B). Adapted from Carmona et al. 24. MVIC:

Searching for a video that shows a cadaver model of hamstrings protecting the ACL, i swear I have seen a video of this somewhere from a biomechanical study, but cant find it. Any help? @TimothyHewett1 any help :)?

We are curious whether this test helps clinicians to spot increased risk of back issues in certain youth cohorts, thoughts?

Any good emg studies that include comparisons of the toes to bar exercise to other trunk/hip flexor exercises?

New study led by Shiqin Chen where we investigate the relationship between muscle (co)activation time-series and lower extremity stiffness -a key component of running economy- as well as joint stiffness during running Key findings in the figure + comments. Link also in comments

Great new paper investigating lower extremity stiffness in running, published in the November 2025 issue of Medicine & Science in Sports & Exercise @MSSEonline

Excited to be speaking in Finland next month alongside some of the top minds in muscle hypertrophy research 💪

NEW PAPER 🏈 Kinetics & Kinematics of Initial Accel 🏃‍♂️💨 Key findings: 🔋Pmax largest relationship w/ 10m performance 💪F0 more important as body mass increases ✅Kinematics associated w/ higher levels of Pmax described @JSportsSci 👇🏼 https://t.co/1LAR7mFkF2

New paper where I argue that injuries such as hamstring strains and ACL injuries may be overuse injuries instead of acute injuries For example, the figure shows that fiber force & length during injury step is not different from many preceding steps FREE paper link in comments

Study Q: I swear Ive seen a study that measures EMG of the different hamstring heads in side jumping vs other directions, but I cant find it. Anyone know of a study with data like this?