12 Nov 2015
The dynamics of rib pain
Dr Anders Vinther presented on this topic at British Rowing’s 2015 Sport Science and Medicine Conference and coauthored a recent editorial with Dr Jane Thornton in the British Journal of Sports Medicine examining the research to date. Vinther, a research physiotherapist at Herlev University Hospital, Copenhagen, Denmark, is widely regarded as a leading expert in the field of rowing rib stress fractures.
Vinther outlines his findings and explains what he believe rowers and coaches should know about rib injuries.
What is a rib stress fracture?
“It is important to know the difference between a stress fracture and a traumatic fracture,” explains Vinther. “The main difference is the number of loadings that result in the actual cracking of the bone. It takes time to develop a stress fracture, whereas a traumatic fracture happens suddenly from a single loading.”
The symptoms of a developing stress fracture can appear early on when a rower feels some discomfort in his or her ribs. Vinther calls this first stage a ‘bone stress injury’. “It is a continuum,” he says, “that starts with a small stress on the bone that develops into micro cracks and then bigger cracks that may turn into an actual fracture”.
Reasons for rib stress fractures
Arguments to explain the frequency of rib stress fractures often focus on the rapid changes to equipment through the 1990s that led to a sharp increase in rib injuries. This includes stiffer, shorter oars and less forgiving composite materials in hull construction. Improvements in the rowing ergometer since then and the increased training volumes and intensities that came with more and more athletes training year-round have also contributed to increased loading.
“The most important thing to note about the ergometer,” continues Vinther, “is the peak loading for each stroke is higher than on the water. Dynamic ergometers, however, produce lower peak loading than stationary ones. There is a pretty strong argument for [them] because they simulate on-water rowing better biomechanically. Stroke frequency will be a little higher to compensate for the lower load.”
Vinther stops short of endorsing any particular brand of dynamic ergometer though, pointing out that there appears to be no major difference in peak loading between the various dynamic systems currently available.
Although switching to a dynamic ergometer set-up may reduce the risk, the stationary ergo doesn’t necessarily deserve blame and using one won’t necessarily give someone a stress fracture. The risk is greater when an athlete is already predisposed to injury through technique, for instance, they use too much upper body early in the stroke. Or there is a training issue, for instance the athlete transfers all of the kilometers they have been doing on the water onto the ergo without a transition period.
Big changes in training constitute one of the greatest risk factors for rib injury. “The beginning of a season is one such period,” says Vinther, “where drastic changes in volume and intensity happen very rapidly. Athletes are changing technique and switching from side to side or sculling to sweep rowing or from the water to the ergometer and maybe loading themselves a little bit differently each stroke.”
“You need to be aware of how many changes you are doing at a time,” cautions Vinther. “They can add up to a lot of stress. Most stress fractures are preceded by some change in training.”
There are also internal risk factors – those related to the individual athlete. These can include muscular imbalance, low bone mineral density and inadequate nutrition or energy intake.
My rib hurts! … now what?
“It is important not to rush bone healing,” Vinther says. “Initially, if you have a lot of symptoms from a rib, you have to stop training because breathing deeply will cause pain. Whenever you feel the slightest pain, take it seriously,” he suggests, although Vinther acknowledges that it is not always so simple. “Elite rowers don’t usually stop because of a little pain, so they need someone to say ‘stop.’”
Strapping, taping or using ice can help manage pain, but the essential thing is to give enough time for the bone to heal. “Usually a simple modification in training allows full healing without complications,” says Vinther.
Prevention is the best medicine
External risk factors can usually be accounted for simply by adjusting load, volume and/or intensity. Switching to a dynamic ergometer or putting your ergo on slides can also help reduce rib pain and the potential progression to a rib stress fracture.
Athletes with any of the internal risk factors can do their best to mitigate these by addressing the root cause. Strengthening muscular imbalances, taking in the proper amount of calories and staying aware of symptoms are part of the process. But what can we do about our bones?
Train the skeleton
“The skeleton positively reacts to training,” Vinther says, “but it needs time to make these adaptations. When no load is exerted, you lose bone strength. Like an astronaut does without the load of gravity, in a similar way when you load the skeleton, it becomes stronger.”
Vinther compares this to strengthening muscles, but on a much longer time scale. “At first there is a small weakening during the remodeling cycle, that lasts two to three months. There is a time lag compared to how your muscles will respond to strength training, whereas the skeleton may take years to adapt accordingly.”
In the end, the essential thing is to listen to your body. “Rowing the semifinals or finals of a major event with fractures can be done,” concludes Vinther, “but then you must stop. The longer you row with pain, the longer it will take to recover.”