Q&A

The published research showing an increase in ACL injuries in young people is observational data. In other words, it gives us a picture of what is happening but does not tell us why. We can postulate reasons but there is no current published evidence to give us a more definitive answer. For example, is it related to increased participation in sport such as football by young people, particularly girls? Is it because young people are coming into sport less ‘physically literate’, a phrase that encompasses the idea of a child learning how to use and control their body.  From a very early age children are spending more time sitting in front of screens playing games and less time being active and playing outside…how is this impacting their risk of injury including ACL ruptures?

Norway has a national injury prevention initiative called Skadefri. Power Up To Play visited Skadefri in Oslo to learn more about their national programme. They have a website and deliver face-to-face training for coaches across Norway by paid staff (our PUTP trainers who run coach education sessions are all volunteers). Skadefri also has a fantastic free-to-use App ‘Get Set-Train Smarter’ https://fittoplay.org/smart-to-know/free-get-set-app-for-download/. The biggest difference is their national initiative was set up with funding from their department of health and attracts large grants to pay for staff to run the initiative and to provide training sessions for coaches and players.

Teenagers should be able to perform a bounding run unless they are carrying an injury. If needed an A skip and/or B skip would be a reasonable starting point with the aim of working up to a bounding run. Bounding run is a more complex movement working on a combination of strength, balance and plyometrics. Control and not speed is the key to all the warm-up components (with the exception of the acceleration/deceleration exercise).

Yes on the warm-up page there is a link to an hamstring strengthening alternative. The link is here: Nordic hamstring alternative. It is slightly easier than the Nordic hamstring exercise and so where possible build up to the Nordic.

There is no published evidence that taping reduces primary non-contact ACL ruptures.

IPP’s are recommended for all young people playing team sport. If someone is hypermobile then increasing core strength, lower limb strength, balance and proprioception (the position of the knee joint at any given time) is absolutely key to help prevent knee injuries.

Yes, as long as they have completed their rehab then they should perform the full IPP to prevent further injury to the operated knee or the contralateral (non-injured) knee.

We do not currently target schools directly, however PE teachers who deliver after-school sports clubs are very welcome to attend training sessions. We have been approached by a number of schools who are interested to find out more and we support them in whatever way we can. Feedback from PE teachers when we set up the initiative is that trying to introduce an IPP into a relatively short PE lesson would be extremely challenging and that it would sit better in the after-school sports clubs where there is more time. If you run after-school club sports and want to attend a training session then please do get in touch!

A young person who sustains a rupture of their ACL will be unable to participate in sport for at least 12 months (nearer 24 months if they are waiting for surgical ACL reconstruction). This has not only a physical impact but a social and psychological impact that can test a young person’s mental resilience. This psychological impact tends to be carried by the parents and the physiotherapists managing their rehabilitation. We’re not aware of any routine psychological support offered at present for amateur athletes. Current, ad-hoc options include online supportive resources and seeking professional support e.g. sports psychologists or via NHS GP. The charity objectives of Power Up To Play are related to primary prevention of ACL injuries.

Power Up To Play’s charity objective is to reduce teenage ACL injuries through regular use of an injury-prevention warm-up. We concentrate on this age group because that is where the research has shown a marked increase in both injury rates and surgical reconstruction rates. We teach a warm-up suitable for secondary school children although some Year 5/6 children would be more than able to perform it.

For primary school age children we firmly believe that the sooner a child expects a warm-up at the beginning of their sport session, the better. We always encourage coaches of younger age groups to introduce a fun warm-up with their younger children so it becomes ‘the norm’. Rugby ACTIVATE has some great resources for younger children with fun, play-based warm-up exercises such as ‘toilet tag’. In football, there is also the ‘FIFA 11+ Kids’ which is aimed at younger primary school-age children. It has been shown to reduce overall injury rates (not ACL injuries because they are much less common in children under 10 years).

The Power Up To Play injury prevention warm-up is based on the PEP (Prevent injury Enhance Performance, Mandelbaum et al.) which was designed to prevent primary non-contact ACL ruptures. It has not been tested specifically in athletes that have already sustained an ACL rupture. However, it is really important that athletes returning to sport following completed of their ACL rehabilitation continue to work on strength, agility and proprioception and should use an injury prevention warm-up routinely.

The evidence for ACL injury prevention programmes being effective has been shown in the 13-26 year age group so we know it is effective in younger adults. There are few studies in older adults and primarily in male adult football players. The results are unclear ie. we do not know if it decreases ACL injury rates. Studies in older adult women are currently lacking.

ACL injury prevention programmes research has studied sports that involve a lot of cutting/change of direction/jumping/landing as we know that these sports pose the highest risk of ACL injury. Therefore we recommend it for any sport where these movements commonly occur.

The understanding around ACL injuries and hormones is not clear from the published literature. There is research showing that the luteal phase of the menstrual cycle may increase risk of ligament injury. However currently there is insufficient evidence that manipulating the menstrual cycle (e.g. through use of the oral contraceptive pill) significantly reduces ACL injury rates. This is an important area for future research.

There is very good evidence for the effectiveness of ACL injury prevention programmes like ours in women. In a systematic review (Huang et al. 2020) looking at the effectiveness of injury prevention programmes (IPPs), a large majority of participants in the studies were female youth athletes. The review found there IPPs had a significant protective effect and reduced ACL injury rates by 53%.

This is an excellent question as it highlights some of the challenges surrounding implementation of an injury prevention programme. If exercises are progressed this has advantages as it maintains interest and continues to challenge the player’s strength and conditioning…however injury prevention programmes that have multiple layers of progression can be harder for grassroot coaches to implement. There are a number of barriers: they only have an hour with their young players, not understanding how to progress/when to progress; needing the same coach to be present each week to know where the team have progressed to; what to do with new arrivals after the rest of the team have progressed the warm-up; time commitment to explain and introduce different exercises. The reality is that this can be off-putting for a grassroot coach so we pragmatically recommend they use a generic, concise, easy, evidence-based warm-up that can be used with every player at any time (barring injury).

If a coach is working with a higher level of team (e.g a performance pathway team) where they have more time each week, they can progress their warm-up to a longer, sport specific warm-up like football’s ’11+’ which has progression of exercises based on an individual’s fitness/ability. These sport specific warm-ups are signposted from the website.

This is difficult to manage if your players are adults. If they are children then a warm-up and cool-down/stretching can be imposed (even if some are reluctant!). The stretching section of the PEP programme is 5 minutes long and although in 2003 when designed it was part of the pre-training warm-up, we recommend coaches use it at the end of a session. This approach is aligned with current evidence that stretching before playing sport has not been shown to have added benefit. It also means that Sections 1-4 (warm-up, strengthening, plyometrics and agility/controlled change of direction) can be completed in only 10-12 minutes before at the start of the session which feels more acceptable for grassroot training sessions which only last one hour. There are ideas to help engage youth players e.g. let players choose a Spotify song for warm-up or stretching.

Power Up To Play focuses on primary ACL injury prevention. There are many other resources available to help guide rehabilitation post-ACL surgery. An example would be https://acltear.info/anterior-cruciate-ligament-rehabilitation/. There is also a recently published narrative review that discusses the evidence supporting key approaches to rehabilitation following ACL injury (Franco, D.et al. Effective Prevention and Rehabilitation Strategies to Mitigate Non-Contact Anterior Cruciate Ligament Injuries: A Narrative Review. Appl. Sci. 2024, 14,9330).
When a young athlete has fully completed their ACL rehabilitation guided by their physiotherapist and return to sport they should regularly use an injury prevention programme that includes strengthening, plyometric, balance and controlled change of direction exercises.