Is Deceleration the Key Element in Vertical Jump Performance to Return to Sport After Anterior Cruciate Ligament Reconstruction with hamstring graft? A prelimnary study

Florian FORELLI, Ayrton MOIROUX--SAHRAOUI, Branis NEKHOUF, Ismail BOUZEKRAOUI ALAOUI, Amaury VANDEBROUCK, Pascal DUFFIET, Louis RATTE, Maciej BIALY, Andreas BJERREGAARD, Jean MAZEAS, Maurice DOURYANG, Alexandre RAMBAUD, IJSPT, 2025

📚 New study:

🔑 Do you adress the deceleration as a key element in vertical jump performance and what does it mean to you?

👥 64 ACLR athletes vs 47 controls

🦵 6 months post hamstring graft

📉 Lower jump height & power

⚡ Hidden deceleration deficits in operated limb

📊 Standard tests miss these asymmetries

🏋‍♂ Rehab must train braking & eccentric control

🎯 Return to sport is not just how high you jump, but how well you absorp forces

hank you for listening

Andreas Bjerregaard

Certificeret kliniker i sportsfysioterapi, IOC-diplom i sportsfysioterapi, Kandidatstuderende i fysioterapi ved Syddansk Universitet – University of Southern Denmark

For more information

Check out

💻Web: https://lnkd.in/dURMF-5g

📸IG: Andreasphysioblog https://lnkd.in/eZb9A2WJ

📚ResearchGate: https://lnkd.in/dd945uWB

🗞️Newsletter: https://lnkd.in/e8MgwUHv

🙋Online ACL Consultation: https://lnkd.in/dbiz6864

This is Season 2, Episode 10 of the Physioblog Podcast, hosted by Andreas Bjerregaard.

In Season 2, I will be presenting all the articles I have been involved in, using the mind-blowing technology of AI podcasting. I think everyone can agree that the AI hosts' voices are much more nice on the ears than my non-native English voice with a thick Danish accent.

Episode 10: 🧠 The Effect of Blood Flow Restriction Training on Quadriceps Activity After Anterior Cruciate Ligament Reconstruction: A Preliminary Randomized Controlled Trial

🔎 Quick Summary of Key Themes:

📚 EMG activity when applying Blood Flow Restriction Training (BFR) on Quadriceps Activity post-ACLR with 80% arterial limb occlusion and 30% MVIC (LL-BFR) against 80% MVIC without BFR (Heavy Loads Resistance Training (HLRT))

📊 Results: HLRT showed higher EMG activity compared to LL-BFR.

💪 Conclusion: HLRT may be more effective in enhancing quadriceps muscle activity post-ACLR. LL-BFR’s potential benefits in reducing joint loading and increasing muscle excitability when HLRT is not possible.

👨‍💻My take away is the start HLRT as early as possible and if not feasible use LL-BFR. When using BFR use enough set and reps. One set is not enough despite feeling hard.

👨🏻‍🏫Amazing author team: Authors Florian Forelli, Camille Nguyen, Jean Mazeas, Georgios Kakavas, Timothy E. Hewett, Andreas Bjerregaard, Vasileios Korakakis, and Alexandre JM Rambaud

Thank you for listening

Andreas Bjerregaard

Certificeret kliniker i sportsfysioterapi, IOC-diplom i sportsfysioterapi, Kandidatstuderende i fysioterapi ved Syddansk Universitet – University of Southern Denmark

For more information

Check out

💻Web: https://lnkd.in/dURMF-5g

📸IG: Andreasphysioblog https://lnkd.in/eZb9A2WJ

📚ResearchGate: https://lnkd.in/dd945uWB

🗞️Newsletter: https://lnkd.in/e8MgwUHv

🙋Online ACL Consultation: https://lnkd.in/dbiz6864

This is Season 2, Episode 9 of the Physioblog Podcast, hosted by Andreas Bjerregaard.

In Season 2, I will be presenting all the articles I have been involved in, using the mind-blowing technology of AI podcasting. I think everyone can agree that the AI hosts' voices are much more nice on the ears than my non-native English voice with a thick Danish accent.

Episode 9: 🧠 Aspetar Clinical Practice Guideline Rehabilitation After Anterior Cruciate Ligament Reconstruction (2023)

This episode covers our clinical guideline paper developed by a fantastic team of clinicians and researchers: Roula Kotsifaki, Vasileios Korakakis, Enda King, Olivia Barbosa, Dustin Maree, Michail Pantouveris, myself (Andreas Bjerregaard), Julius Luomajoki, Jan Wilhelmsen, and Rodney Whiteley.

🔎 Quick Summary of Key Themes:

🦵 Timing & Structure

✅ Modalities

🏁 Exercise Initiation

💪 Strength & Motor Control Training

🚀 Return to Activities

Andreas Bjerregaard

Certificeret kliniker i sportsfysioterapi, IOC-diplom i sportsfysioterapi, Kandidatstuderende i fysioterapi ved Syddansk Universitet – University of Southern Denmark

For more information

Check out

💻Web: https://lnkd.in/dURMF-5g

📸IG: Andreasphysioblog https://lnkd.in/eZb9A2WJ

📚ResearchGate: https://lnkd.in/dd945uWB

🗞️Newsletter: https://lnkd.in/e8MgwUHv

🙋Online ACL Consultation: https://lnkd.in/dbiz6864

This is Season 2, Episode 8 of the Physioblog Podcast, hosted by Andreas Bjerregaard.

In Season 2, I will be presenting all the articles I have been involved in, using the mind-blowing technology of AI podcasting. I think everyone can agree that the AI hosts' voices are much more nice on the ears than my non-native English voice with a thick Danish accent.

Episode 8: Criteria-Based Decision Making for Introducing Open Kinetic Chain Exercise after-ACL Reconstruction: A Scoping Review, driven by a fantastic team of clinicians and researchers: Florian Forelli, Jean Mazeas, Vasileios Korakakis, Haashim Ramtoola, Amaury Vandebrouck, Pascal Duffiet, Louis Ratte, Georgios Kakavas, Ismail Bouzekaroui Alaoui, Maurice Douryang, Andreas Bjerregaard, Jérôme Riera and Alexandre J. M. Rambaud

📊 Short summery

🦵 OKC After ACLR – Key Highlights

✅ OKC exercises are safe & boost quad strength

❌ No evidence they increase graft laxity

⏱️ 81% of studies use time-based criteria (median: 15 days)

🔍 Only a few include clinical signs like:

• ROM ≥ 90–100°
• 🚶‍♂️ Walking without crutches
• 😌 Pain < 2–3
• 💧 No joint effusion
• 🔄 Full quad activation

⚠️ Lack of standardized criteria = confusion in clinical practice

💡 Recommendation: Shift to a criteria-based rehab approach

🧱 Early OKC + controlled loading = stronger quads & better graft health

🔁 Delayed OKC = may miss strength gains

Who

Andreas Bjerregaard

Certificeret kliniker i sportsfysioterapi, IOC-diplom i sportsfysioterapi, Kandidatstuderende i fysioterapi ved Syddansk Universitet – University of Southern Denmark

For more information

Check out

💻Web: https://lnkd.in/dURMF-5g

📸IG: Andreasphysioblog https://lnkd.in/eZb9A2WJ

📚ResearchGate: https://lnkd.in/dd945uWB

🗞️Newsletter: https://lnkd.in/e8MgwUHv

🙋Online ACL Consultation: https://lnkd.in/dbiz6864

This is Season 2, Episode 7 of the Physioblog Podcast, hosted by Andreas Bjerregaard.

In Season 2, I will be presenting all the articles I have been involved in, using the mind-blowing technology of AI podcasting. I think everyone can agree that the AI hosts' voices are much more nice on the ears than my non-native English voice with a thick Danish accent.

Episode 7: Quadriceps Activation After Anterior Cruciate Ligament Reconstruction: The Early Bird Gets the Worm!, driven by a fantastic team of clinicians and researchers.

📊 Abstract

Starting Strong in ACL Rehab
A strong start in ACL rehab is crucial for a successful return to play and to avoid long-term issues like increased OA risk, reduced quality of life, and diminished function

However, Arthrogenic Muscle Inhibition (AMI) can delay this good start by hindering quadriceps activation. This article covers early intervention strategies to address AMI for quicker recovery and better outcomes.

What is AMI?
AMI reduces motor neuron availability and voluntary activation, often due to pain, patellar issues, swelling, and lack of quadriceps contraction.

Therapeutic Intervention Classification:

🦵 Grade 0: Normal contraction.
🦵 Grade 1: Inhibited contraction, no extension deficit.
🦵 Grade 2: Inhibited contraction, knee extension deficit due to hamstring contracture.
🦵 Grade 3: Chronic extension deficit from posterior capsular retraction.
These classifications are based on clinical experience with limited validation.

Clinician Observations:

Minimal activation: SLR without lag, sensing quadriceps contraction.
Adequate activation: Full knee extension, qualitative quadriceps contraction, and patient feedback.
Fast activation: Important in later rehab phases, especially for plyometric activities.


AMI Treatment Modalities:

Muscle interventions: BFR, hamstring fatigue exercises.
Brain interventions: Virtual Reality, Cross Education Therapy, EMG Biofeedback, Motor Imagery, Vibration.
Nerve interventions: NMES, TENS, Cryotherapy, Percutaneous Electrical Stimulation.

Find it here: 

Ref

MOIROUX—SAHRAOUI A, FORELLI F @flovarium @centre_orthosport , MAZEAS J @je_maze , RAMBAUD AJ @alexandrejmrambaud , BJERREGAARD A @andreas.bjerregaard , RIERA J @jeromeriera 

Who

Andreas Bjerregaard

Certificeret kliniker i sportsfysioterapi, IOC-diplom i sportsfysioterapi, Kandidatstuderende i fysioterapi ved Syddansk Universitet – University of Southern Denmark

For more information

Check out

💻Web: https://lnkd.in/dURMF-5g

📸IG: Andreasphysioblog https://lnkd.in/eZb9A2WJ

📚ResearchGate: https://lnkd.in/dd945uWB

🗞️Newsletter: https://lnkd.in/e8MgwUHv

🙋Online ACL Consultation: https://lnkd.in/dbiz6864

This is Season 2, Episode 6 of the Physioblog Podcast, hosted by Andreas Bjerregaard.

In Season 2, I will be presenting all the articles I have been involved in, using the mind-blowing technology of AI podcasting. I think everyone can agree that the AI hosts' voices are much more nice on the ears than my non-native English voice with a thick Danish accent.

Episode 6: Knee strengthening after surgery: A comprehensive analysis using key performance indicators, driven by a fantastic team of clinicians and researchers.

📊 Abstract

This article provides a comprehensive analysis of knee strengthening post-surgery, focusing on key performance indicators (KPIs) essential for recovery and performance enhancement. The study delves into the importance of range of motion (ROM), load management through repetitions maximum (RM) and velocity-based training (VBT), speed variations, repetition schemes for hypertrophy and strength, and the assessment of pain, inflammation, and effusion. Emphasis is placed on dynamic alignment, muscle activation, and rate of perceived exertion (RPE) to tailor individualized rehabilitation programs. The integration of these KPIs ensures a balanced approach, enhancing muscle strength and joint integrity while minimizing injury risk. Regular monitoring and adjustments based on these indicators are recommended to optimize outcomes and ensure sustained progress in knee function and overall mobility

Find it here: 

Florian Forelli, Jean Mazeas, Mathias Nielsen-Le Roux, Ayrton Moiroux Sahraoui, Nicholas Miraglia4, Maciej Bialy, Ismail Bouzekraoui Alaoui, Georgios Kakavas, Andreas Bjerregaard, Maurice Douryang, 2025 Knee strengthening after surgery: A comprehensive analysis using key performance indicator

Andreas Bjerregaard

Certificeret kliniker i sportsfysioterapi, IOC-diplom i sportsfysioterapi, Kandidatstuderende i fysioterapi ved Syddansk Universitet – University of Southern Denmark

For more information

Check out

💻Web: https://lnkd.in/dURMF-5g

📸IG: Andreasphysioblog https://lnkd.in/eZb9A2WJ

📚ResearchGate: https://lnkd.in/dd945uWB

🗞️Newsletter: https://lnkd.in/e8MgwUHv

🙋Online ACL Consultation: https://lnkd.in/dbiz6864

This is Season 2, Episode 4 of the Physioblog Podcast, hosted by Andreas Bjerregaard.

In Season 2, I will be presenting all the articles I have been involved in, using the mind-blowing technology of AI podcasting. I think everyone can agree that the AI hosts' voices are much more nice on the ears than my non-native English voice with a thick Danish accent.

Episode 5: Can Hamstring Dynamic Ratio Help Return To Sport Decision Making After Hamstring Injury, 2024, driven by a fantastic team of clinicians and researchers.

📊 The study aimed to determine whether the dynamic ratio of hamstring muscle activity (biceps femoris [BF] vs. medial hamstrings [MH]), measured via electromyography (EMG), correlates with the isokinetic hamstring-to-quadriceps strength ratio—a common tool in rehabilitation and return to sport (RTS) decisions.

🤾🏼‍♂️No correlation was found between the dynamic EMG BF/MH ratio and the isokinetic strength ratio in healthy subjects.

Find it here: 

Jean Mazeas, Freddy Nkuamsanbu, Mickael Passe – Coutrin, Florian Forelli, Georges Kakavas, IsmailBouzekraoui, Andreas Bjerregaard, Nikolaos Malliaropoulos, Maurice Douryang, Can Hamstring Dynamic Ratio Help Return To Sport Decision Making After Hamstring Injury, 2024

Andreas Bjerregaard

Certificeret kliniker i sportsfysioterapi, IOC-diplom i sportsfysioterapi, Kandidatstuderende i fysioterapi ved Syddansk Universitet – University of Southern Denmark

For more information

Check out

💻Web: https://lnkd.in/dURMF-5g

📸IG: Andreasphysioblog https://lnkd.in/eZb9A2WJ

📚ResearchGate: https://lnkd.in/dd945uWB

🗞️Newsletter: https://lnkd.in/e8MgwUHv

🙋Online ACL Consultation: https://lnkd.in/dbiz6864

This is Season 2, Episode 4 of the Physioblog Podcast, hosted by Andreas Bjerregaard.

In Season 2, I will be presenting all the articles I have been involved in, using the mind-blowing technology of AI podcasting. I think everyone can agree that the AI hosts' voices are much more nice on the ears than my non-native English voice with a thick Danish accent.

Episode 4: Prevention of Overhead Shoulder Injuries in Throwing Athletes: A Systematic Review driven by a fantastic team of clinicians and researchers.

📊 The aim of our review was to determine whether prevention by strengthening the kinetic chain can have an impact on the rate of shoulder injury in overhead pitching athletes. 

🤾🏼‍♂️Conclusions: It is important to integrate core stability work and lower limb strengthening to minimize excessive stress on the shoulder complex, while optimizing force production and performance.

🤽🏻Clinical note: Don’t forget the entire kinetic chain when treating throwers.

Find it here: 

Moiroux–Sahraoui A, Mazeas J, Delgado N, Le Moteux C, Acco M, Douryang M, Bjerregaard A, Forelli F. Prevention of Overhead Shoulder Injuries in Throwing Athletes: A Systematic Review. Diagnostics. 2024; 14(21):2415. https://doi.org/10.3390/diagnostics14212415

Andreas Bjerregaard

Certificeret kliniker i sportsfysioterapi, IOC-diplom i sportsfysioterapi, Kandidatstuderende i fysioterapi ved Syddansk Universitet – University of Southern Denmark

For more information

Check out

💻Web: https://lnkd.in/dURMF-5g

📸IG: Andreasphysioblog https://lnkd.in/eZb9A2WJ

📚ResearchGate: https://lnkd.in/dd945uWB

🗞️Newsletter: https://lnkd.in/e8MgwUHv

🙋Online ACL Consultation: https://lnkd.in/dbiz6864

This is Season 2, Episode 3 of the Physioblog Podcast, hosted by Andreas Bjerregaard.

In Season 2, I will be presenting all the articles I have been involved in, using the mind-blowing technology of AI podcasting. I think everyone can agree that the AI hosts' voices are much more nice on the ears than my non-native English voice with a thick Danish accent.

Episode 3: Translation, cross-cultural adaptation, and clinimetric properties evaluation of the Danish version of the Anterior Cruciate Ligament - Return to Sport after Injury scale (ACL-RSI)

😁 I’m really happy to see our article “Translation, cross-cultural adaptation, and clinimetric properties evaluation of the Danish version of the Anterior Cruciate Ligament – Return to Sport after Injury scale (ACL-RSI)” out🎉

📎 https://pubmed.ncbi.nlm.nih.gov/39612538/

This publication is my first article as 1st author, and I can’t express enough appreciation to the author team Esben Kjeldgaard, Kasper Nordahl Wøbbe, Cecilie Køllner Olsen, Kristoffer Barfod & @Vasileios Korakakis for their continuous support🙏. It is the result of 4 years of work, including almost 3 years of enrolling over 100 ACL patients in Denmark who were between 8-24 months post-op. Thanks to all the clinicians who have helped. Thanks to all the patients who took the time to fill out the questionnaires. Thanks to Lasse Ishøi and Behnam Liaghat for listening and offering advice when I’ve been panicking.

📚 The ACL-RSI questionnaire is a specific tool for assessing psychological readiness for return to sport, and our article focused on the translation, cross-cultural adaptation, and evaluation of the clinimetric properties of the Danish version of the Anterior Cruciate Ligament – Return to Sport after Injury scale (ACL-RSI).

📚 We followed all fundamental steps in the process and found excellent internal consistency (Cronbach’s alpha 0.957) and test-retest reliability (ICC = 0.96). We also validated the questionnaire against KOOS and K-SES as they are commonly used in ACLR. We also confirmed the unidimensionality of the scale, and did not observe any floor or ceiling effects. The mean time of completion of the questionnaire is 4.5 minutes.

We concluded that ACL-RSI was successfully translated and adapted into Danish, demonstrating good psychometric properties. It serves as a useful tool for clinicians to assess psychological readiness for RTS in athletes post-ACLR.

👨‍🎓 My own take on the article:

Remember to use objective testing and questionnaires as part of your test battery. Don’t only test at the end of the rehab, but continuously throughout the rehab. In our article, our recruitment strategy, our population, and other limitations have properly influenced our results. However, I am very concerned about the low scores we found in the Danish translation. It’s great that we now have a properly translated questionnaire, but we need to reflect on the results we are getting from our individual patients and have clear and realistic targets for what we expect moving forward. Maybe one questionnaire isn’t enough, perhaps different questionnaires at different stages. My clinical message is to use questionnaires as part of your rehabilitation journey.

Andreas Bjerregaard

Certificeret kliniker i sportsfysioterapi, IOC-diplom i sportsfysioterapi, Kandidatstuderende i fysioterapi ved Syddansk Universitet – University of Southern Denmark

For more information

Check out

💻Web: https://lnkd.in/dURMF-5g

📸IG: Andreasphysioblog https://lnkd.in/eZb9A2WJ

📚ResearchGate: https://lnkd.in/dd945uWB

🗞️Newsletter: https://lnkd.in/e8MgwUHv

🙋Online ACL Consultation: https://lnkd.in/dbiz6864

This is Season 2, Episode 2 of the Physioblog Podcast, hosted by Andreas Bjerregaard.

In Season 2, I will be presenting all the articles I have been involved in, using the mind-blowing technology of AI podcasting. I think everyone can agree that the AI hosts' voices are much more nice on the ears than my non-native English voice with a thick Danish accent.

Episode 2: Stay in the Game: Comprehensive Approaches to Decrease the Risk of Sports Injuries

In this episode, I present 🏋️‍♂️ Stay in the Game: Comprehensive Approaches to Decrease the Risk of Sports Injuries

📝 Forelli F, Moiroux-Sahraoui A, Nielsen-Le Roux M, Miraglia N, Gaspar M, Stergiou M, Bjerregaard A, Mazeas J, Douryang M. 🔗 DOI: 10.7759/cureus.7646112415

Background: This article is asking you to check all your boxes before returning a player for sport after an injury?

In this article, we present a detailed framework for preventing and managing sports injuries, emphasizing a holistic approach that integrates:

💪 Physical strategies

🧠 Psychological strategies

🥗 Nutritional strategies

By checking all the boxes ✔️ within this framework, athletes 🏃‍♂️, coaches 🏅, and medical teams 🩺 can work together to:

🔄 Minimize injury recurrence

🚀 Enhance long-term performance

🏆 Ensure athletes remain competitive and resilient