BEETROOT for athletes: stay on the road!

Here’s an uncomfortable fact; high training volumes are strongly associated with an increased risk of an overuse injury. So if you’re an athlete who  suffers from recurring injuries and wants to know why, or you’re just keen ensure you stay injury free, sports physiotherapist Chris Mallac provides an insight in to the key causative factors in overuse injuries, and how athletes can use this knowledge to stay on the road.

This article is not a story on the merits of beetroot juice and how, thanks to its endurance enhancing properties, it is apparently a favourite tipple among Team Sky riders. Rather, this is a story of a sinking ship (pardon the Gilligan’s Island reference). However, the sinking ship in this discussion is the overuse injuries suffered by endurance athletes, both professional and recreational.

In the same way we can plug the holes in a sinking ship, we can also plug the holes that create overuse injuries. And for the sports enthusiast out there, overuse injuries are common. For example, just a few common examples include plantar fasciitis (foot pain in the base of the foot), shin splints, patellofemoral (knee) pain, hamstring tendinopathy, grumbly lower backs, shoulder impingements – the list goes on.

But before you run off and see a physiotherapist to evaluate your overuse injury, or spend hours on ‘Dr Google’ trying to work out why your Achilles tendon hurts, it’s worth spending a little while unpacking the common causes of overuse injuries.

What is in BEETROOT?

The acronym we use to understand the causative factors in overuse injuries is B.E.E.T.R.O.O.T (see figure 1). The best way to explain the eight common factors that cause an overuse injury is to use a few sports as examples and some common injuries in those sports. Just be aware that you may have one of these factors at play or more than one – i.e a few factors that coexist together.

FIGURE 1: BEETROOT ACRONYM EXPLAINED

B is for Biomechanics

Although we mentioned not running straight off to the physio, ironically, this is where you may really need the help of a physiotherapist or corrective exercise specialist. It may seem bizarre but many of us can display terrible movement mechanics, yet be unaware, and think these movement patterns are normal. Having someone watch us and even film our movement can certainly help understand where the body is falling apart when it comes to biomechanics. Therefore, a keen eye watching our movement may help to unpack how poorly we do actually move in certain activities.

For runners, a common complaint is shin splints. Examples of how biomechanics plays a role in shin splints include movement faults such as over pronation (tipping inwards) of the feet (see figure 2), which places extra strain on the shin muscles that control pronation. You may need a physiotherapist or podiatrist to help you with this.

For the swimmer, having an inflexible thoracic spine is an accident waiting to happen at the shoulder. Swimmers need great thoracic extension to get their reach in the water. If they don’t have thoracic extension, then the shoulder needs to over flex and this may compress the rotator cuff and set up an impingement in the shoulder. Working on developing thoracic extension when it is lacking (see figure 3) is therefore important for swimmers.

For cyclists, stiff hip flexion (when the knee moves towards chest) will place extra force on the lower back because the lower back will have to compensate to overcome hip tightness. In essence, biomechanics relates to the inherent movement faults (patho-mechanics) or structural faults (patho-anatomy) that may predispose an athlete to an injury and these form a large part of why athletes sustain overuse injuries.

FIGURE 2: OVER PRONATION DURING RUNNING

FIGURE 3: THORACIC CHEST EXPANSION FOR SWIMMERS

E is for Equipment

The obvious equipment fault in running is running shoes. These may be inappropriate or simply worn down. Two of the most common running shoes used by runners are the Asics Gel Kayano and the Asics Gel Nimbus. Both are made by Asics, but they are inherently very different shoes. If a runner is used to running in a Kayano (a traditional supportive shoe for the over pronator) but switches to a Gel Nimbus (a classic mobility shoe for a runner with a stiff foot), then the sudden change in shoe may set them up for a plantar fascia problem or a shin splint.

Consider too the cyclist who leaves his $5000 Cannondale at the bike shop for service, where the technician accidentally resets the seat height ever so slightly higher. The unaware cyclist may jump back on the bike and in a few weeks start to wonder why their Achilles tendon is so sore! The small change in bike set up may predispose them to an overuse injury. This is why a lot of physios now specialise in bike set up consultations, as a small change in a bike set up may predispose a cyclist to an overuse injury.

For the swimmer, the killer of the shoulder is the swimming paddle (see figure 4). Paddles are worn to make the swimmer pull through the water with more force and to develop a ‘feel’ for the water. Swim coaches love these to improve the stoke power of the swimmer. But overzealous use of swim paddles in training may create extra forces across the shoulders that may stir up the soft tissues in the shoulder.

FIGURE 4: SWIM PADDLES

E is for Environment

In the running athlete, the surfaces underfoot have a huge bearing on the incidence of overuse injuries runners may suffer in the lower limb. You will no doubt know that tarmac is harder than grass. However, you might be surprised to discover cement and/or paved pathways and bike tracks are significantly harder than tarmac. So if a runner is used to running on roads and then switches to running on the pavement (eg for safety reasons or because of a move from the country to the city), the change in surface may aggravate shin injuries and foot injuries. Another example comes from triathlon. Triathletes often need to swim on open water such as lakes and the ocean. However, the way a triathlete swims in ocean is very different to a pool. For a start, oceans don’t have a black line to follow so often the swimmer in the ocean has to lift their head a lot to see where they are going. This places a much larger force on the shoulder. Similarly, oceans usually have a slight swell or ‘chop’ and the swimmer has to lift their arm higher to clear waves. This higher recovery position also places extra stress on the shoulder. A sudden switch from pool to open-water swimming then can easily push swimmers into an overuse injury at the shoulder.

T is for Training

This is arguably the biggest factor in overuse injuries – and probably what you think of when you conjure up images of overuse injuries. What matters is how much an athlete trains and with how much intensity. Sudden changes in volume and intensity can set up an overuse injury quite rapidly.

For example, if someone is training for an upcoming marathon and they ramp up the miles quickly, then this can set them up for a host of lower limb soft tissue injuries. Another is in swimmers in the USA, who tend to ramp up their training prior to Christmas. This can lead to a shoulder overuse injury in January.

High-performance coaches and the sports medicine world have recently developed some clever scientific studies that show exactly how ‘spikes’ in training volume and/or intensity can lead to injuries. The tool used in this context is the ‘Acute on Chronic Work Ratio’ or ‘ACWR’. It is way beyond the scope of this article to describe this concept, but in short, it describes how acute workloads compared to chronic workloads can be a precursor to certain types of injuries.

The ACWR uses a rolling 4-week average to determine the chronic workload (some use a 3-week average) and the following week’s load (acute load) is compared against the average of the preceding four weeks. If the ratio of the acute (what you’ve just done) to chronic (what you’ve done in the four weeks prior to that) workload is greater than 1.3 or less than 0.8, then this may set up the athlete for an injury in the following weeks (see figure 5).

FIGURE 5: RISK OF INJURY RELATING TO ACWR^{Br J Sports Med. 2016 Apr;50(8):471-5}

Let’s use the runner as an example and say we are using kilometres run in a week as the measure of workload. Suppose we have:

• Week 1: 40km
• Week 2: 45km
• Week 3: 48km
• Week 4: 54km

The average of these four weeks is (40+45+48+54 divided by 4) = 46.75 km. Now let’s say that in week 5 the runner covers 60km. The ACWR is calculated as: 60/46.75 = 1.28. This is just under the threshold of the 1.3, so this shouldn’t be a problem.

However, had the runner covered 70km in week 5, the ACWR would be 70/46.75 = 1.50; this jump in volume would greatly increase the risk of an injury in the following weeks. Other ways of measuring metrics are to use distance in swimming or distance in cycling. However, it’s not just about training volume but also about intensity. Another measure is to use the ‘sessional RPE’ or ‘perceived exertion’ multiplied by the time of the session. RPE is a subjective rating on how hard a training session is. It is most commonly measured on a scale of 0-10 with 0 being asleep and 10 being the hardest thing you could do (see figure 6).

As an example, let us use an athlete who trains a few times a week and often competes on Saturdays. Here’s a sample week:

• Monday Off
• Tuesday Training (60 minutes x 5/10 RPE) = 300 units
• Wednesday Gym session (45 minutes x 6/10) = 270 units
• Thursday Training (45 minutes x 6/10) = 270 units
• Friday Off
• Saturday Compete (90 minutes x 8/10) = 720 units
• Sunday Off

The weekly total of ‘duration x RPE’ units is now (300+270+270+720) = 1560. Now let’s add this week (which we will call week 4) to some three previous weeks. We get:

• Week 4 1560
• Week 3 1700
• Week 2 1800
• Week 1 1500

The chronic workload for these four weeks is now (1560+1700+1800+1500/4) = 1640. If week 5 has a score of 1800, then the ACWR is now 1800/1560 = 1.15. Again, this is safe and acceptable. But if week 5 scores 2100 (easily done if the Tues/ Thurs training sessions are significantly harder), the ACWR becomes 1.35, which is getting into dangerous territory. A recommendation for all athletes therefore is to keep a track of ACWR – either manually, or with the use of an automated spreadsheet, which is easily created in Excel.

FIGURE 6: RPE SCALE

R is for Recovery

This concept fits alongside the T-Training factor. Poor recovery behaviours and doing too much too often does not allow adaptation in the bones, muscles and tendons and this may lead to an overuse injury. Recovery strategies such as compression garments, ice baths and massage can have a positive effect on adaptation and recovery and ward off overuse injuries. Therefore, poor recovery practices or insufficient attention to recovery may lead to an overuse injury.

O is for Older

It is accepted that certain age groups are more prone to certain overuse injuries. Younger athletes who train like older athletes are more prone to bone stress injuries such as stress fractures. Therefore, a young 19-year old runner who ramps up their training volume may start to develop a stress response in bones – for example in the tibia of the legs and metatarsal of the feet.

Conversely, older athletes are more prone to ‘white tissue degenerative’ injuries. An inevitable consequence of getting older is that the ‘white tissues’ in the body start to change (for the worse) from the age of approximately 30. The white tissues are the tendons, fascia, meniscus in the knee, discs between the vertebra in the spine and cartilage that surrounds joints.

Because of hormonal changes that occur due to aging, these tissues become weaker and start to change and breakdown. This process does not happen overnight but does slowly start to degrade the white tissues over time. Therefore, a 50year old marathon runner is more prone to tendon injury than a 20 year old. This is not a modifiable risk factor as we cannot make ourselves younger. We simply have to accept that as we get older we cannot tolerate the same workload we could when we were 25 years of age.

O is for Overreaching

This is a fancy name that takes into account ALL the stress factors in the athlete’s life that may impact stress responses and effect adaptation and recovery. Examples of stress factors may be work-related stress, family stress such as the death of loved one, relationship stress, financial stress and all other forms of physical/emotional/ intellectual stress.

The effect of stress on the body is that the body releases cortisol which is a hormone that degrades tissues. High levels of stress have been linked to the development of overuse injuries due to the hormone imbalances that may then affect tissues such as tendons and muscle. A prospective evaluation of major stress events in one’s life often shows that they preceded the development of an overuse injury, highlighting stress as a causative factor.

T is for Threats

Threats relate to medical conditions and other random factors that have been implicated in overuse injuries. Particular types of overuse
injuries have known risk factors. These provide a ‘threat’ to the potential to develop an overuse injury. Examples include:

• Diabetics, who have a greater chance of developing tendiniopathy.
• Women (especially older women), who have a greater chance of developing stress fractures.
• Fluoroquinolone antibiotic use (eg Ciprofloxacin, Levofloxacin etc), which increases the chance of developing tendinopathy.

In summary

For the athlete or the weekend warrior, overuse injuries are a common problem suffered in the course of training and competing in one’s chosen sport. Many factors contribute to the occurrence of an overuse injury. Using the BEETROOT acronym is an easy way for the poor sufferer to determine which factors are the major contributors to their overuse injury. If some of these are identified and then modified, then the athlete may be back into training in no time.

PRACTICAL RECOMMENDATIONS

In addition to the tips given above, you should think about the following:

• *It is not what you do that causes the problems. It is how you get there that does. For the coach and athlete, look at any recent changes in any of the eight factors mentioned above.
• *The holy grail of endurance training has always been training variables such as volume. The athlete and coach are fixated on the numbers of miles run, kilometres cycled and laps swum. Increases in volume are necessary to force an adaptive process. But these jumps need to be incremental. Remember the 1.3 to 0.8 ACW ratio.
• *Often, more than one factor from the eight mentioned above are implicated in overuse injuries. It takes a savvy athlete or coach to be able to unravel those eight factors and ask enough questions to work out which are the most relevant.
• *If you suspect that more than one factor is involved, the suggestion is to only modify one aspect at a time – and maybe give that modification a 4-week trial period. If you change everything all at once, then you won’t really know which factor you changed produced the greatest benefit if you suddenly get better. Knowing this is particularly important if you suffer the same problem again at a later date.