Back in 350 BC, Aristotle commented that Olympic victors were those who
did not squander their powers by early overtraining. Few have heeded these
words; overuse injuries remain front and center in our sports populations.
In the 1980s when we were investigating wrist pain in competitive gymnasts,
we noticed something strange: In many of these adolescent athletes, the
distal radius was short in proportion to the ulna, creating an impingement
of the triangular fibrocartilage.
These patients were training more than 24 hours per week. We soon realized
that overuse can suppress the physis, and not only in the wrist. It's
one reason that many of the best female gymnasts stand only about 4'10".
The Manifestation of Overuse Injuries
The experience taught me that overuse injuries can manifest themselves
in unexpected ways, so sports physicians must constantly be on the lookout.
Improvement as an athlete requires applying the optimum training load to
bring about adaptation without causing harm.
That formula changes with the athlete's age and varies from sport to
sport. While gymnasts' growth is stunted, 14- to 16-year-olds may
end up with longer arms. In these athletes, the adaptations may make them
better at their sports.
But in others, overuse can cause injuries that stop them in their tracks.
This includes
Osgood-Schlatter disease, an apophysis resulting from repetitive quadriceps contraction through
the patellar tendon at its insertion upon the skeletally immature tibial
tubercle. We see this a lot in September when kids return to school sports
but are not properly adapted to the load.
In runners this time of year, we also tend to see stress fractures. These
are caused by a sudden increase in the dose of running. The intensity,
frequency, and duration determines the dose. And according to Wolff's
law, for every stress, the bone gets bigger and stronger. A stress fracture
occurs when the dose of stress exceeds the bone's capacity to adapt.
Injury-Prevention Routines
Cross-country and track athletes must maintain a high-enough dose over
the summer such that they can adapt to the training regimen in the fall.
Working at UCLA in the late 1980s with Olympic medalist sprinters such
as Florence Joyner, Danny Everett, Steve Lewis, and Mike Marsh, and with
coaches like John Smith, I learned that every step up in intensity must
be followed by a decrease. We called this "cyclical progression."
For example, for runners, every increase of two tenths of a mile should
be followed by a decrease of one tenth in the next run. A runner who starts
at 3.0 miles should run 2.9 the next time, then 3.1, then 3.0, then 3.2,
then 3.1, then 3.3 and so on.
Injury prevention warm-up routines such as the Fédération
Internationale de Football Association (FIFA) 11+ program can also reduce
the risk for overuse injuries. In one study,[1]
the FIFA 11+ reduced overuse injuries among teenage female soccer players by 47%.
Children run a lower risk for overuse injuries when they avoid superspecialization.[2] They should not focus on a single sport and instead alternate and experiment
with multiple sports, at least until high school. Within sports, reasonable
restrictions can also help prevent overuse injuries. In soccer, for example,
I recommend not heading the ball below age 10 and only limited heading
until age 14.
Overuse injuries are more common in female athletes and
are especially likely in young women who are suffering from the female
athlete triad: low energy availability with or without disordered eating, menstrual dysfunction,
and low bone mineral density.[3] Because they may make less estrogen, their bones may be weaker and more
susceptible to stress fractures. Older female athletes may run a similarly
elevated risk for stress
fractures if their estrogen levels have declined because of normal aging.
Because of problems like this, I look at the athlete in a very comprehensive
manner. In our women's national soccer team, we frequently check dietary
vitamin D and calcium.
Low vitamin D levels have been associated with stress fractures.[4]
When Pain Does Not Equate Gain
One of the challenges for coaches and other sports professionals is that
athletes vary in their ability to adapt to similar doses of exercise.
For example, if you're a cross-country coach for a high school team,
you'll have 14-year-olds who look like they're 12 and 14-year-olds
who look like they're 20. The athletes who have not gone through puberty
will experience pain at a lower dose of exercise than those who have gone
through puberty.
Of course, not every pain means that the athlete needs to stop training.
Some pain is simply a symptom of healthy adaptation. When it's a stress
injury but not a stress fracture, athletes can back off, drop down in
progression, cross-train, and allow the pain to get better. These are
scalable processes.
But a very sharp pain means that the athlete should take a pause. And so
does pain that progresses in its timing, from during the activity to after
the activity and finally to before the activity. This sequence often signals
a stress fracture.
The most common stress fractures cause pain in the hip, the thigh, the
tibia, and the outside of the foot. Significant hip pain in a young female
runner can be almost an emergency. I've often seen femoral neck stress
fractures go on to become displaced fractures. This can affect the blood
supply and cause avascular necrosis, leading to collapse of the femoral
head. That's a significant problem in a young person. So when female
athletes come to me with this type of pain, I get MRI scans as soon as possible.
Likewise, when an athlete reports tibial pain, I treat it as a stress fracture
until proven otherwise. Fifth metatarsal fractures also start with significant
pain and can quickly result in a displacement. When we see that dreaded
line in the middle of the fifth metatarsal face, we're seeing something
that has to be fixed right away.
Managing the dose of a training program can prove difficult at any level
of recreation or competition. When I worked with US Navy Seals, I found
that many were so aggressive, they wouldn't admit pain. They would
get stress fractures and then get cut from the program.
On the other end of the continuum, I have worked with the LA Leggers running
club. Some members start the season overweight or with low levels of vitamin
D or estrogen. In this population, stress fractures can occur with training
regimens of only a few miles per week. If you go from 0 to 6 miles per
week, you can get the same effects as going from 30 to 90 miles per week.
That's why I tell all of the athletes I work with that the maxim "no
pain, no gain" doesn't apply.
References
- Soligard T, Myklebust G, Steffen K, et al. Comprehensive warm-up programme
to prevent injuries in young female footballers: cluster randomised controlled
trial. BMJ. 2008;337:a2469.
-
Myer GD, Jayanthi N, Difiori JP, et al. Sport Specialization, Part I: Does
early sports specialization increase negative outcomes and reduce the
opportunity for success in young athletes? Sports Health. 2015;7:437-442.
Abstract
-
Brown KA, Dewoolkar AV, Baker N, Dodich C. The female athlete triad: special
considerations for adolescent female athletes. Transl Pediatr. 2017;6:144-149.
Abstract
-
Burgi AA, Gorham ED, Garland CF, et al. High serum 25-hydroxyvitamin D
is associated with a low incidence of stress fractures. J Bone Miner Res.
2011;26:2371-2377.
Abstract