WorldTeam Winter fat or fragile bones? Lotto Soudal riders under the Dexa scan.
In the build-up to each new cycling season, the Lotto Soudal riders undergo a series of medical tests. One of these tests is the Dexa scan (Dual-Energy X-ray Absorptiometry), a screening that is done multiple times a year and yields valuable information in order to optimise the performance of the Lotto Soudal riders. Wim Van Hoolst, coach at Energy Lab, explains the importance of this scan.
What exactly is a Dexa scan?
"A Dexa scanner is a device in which riders take place in cycling clothing or sports outfit. During some ten minutes, the rider is scanned from head to toe with a laser which uses X-rays to analyse the body composition. That way, we get a very extensive image of the athlete in a very short period of time. In addition to that, the Dexa scan provides the right values every single time. It is like the gold standard to determine body composition", says Wim Van Hoolst.
What is the purpose of a Dexa scan?
A Dexa scan provides an insight into three key values which will be used to adjust training and nutrition schemes in order to optimise the rider's performance.
Body fat mass
Wim Van Hoolst: "First and foremost, there is the body fat mass, which is measured accurately to the nearest gram. This is the number of kilos of body fat. For an athlete, it is for example disadvantageous to have a fat percentage above ten percent during the winter period. Why? Because it takes energy to get rid of this fat mass again, and this energy is something the riders heavily need during training from mid-December onward. In this period, the training intensity and volume will be seriously increased. So, it is important that the energy supply is always sufficiently replenished to be able to have a qualitative training session the next day. If you still need to lose weight during that period, you create a negative energy balance, which in turn is detrimental to your recovery."
"Ten percent is a good target figure for the upper limit, but also riders with a fat percentage that's too low are closely monitored. A value that's too low also has a negative impact on the ability to recover, because the hormones that improve recovery - such as testosterone - are produced by fat. Therefore, the results of these scans are always shared with Damien Pauquet, the dietician of the Lotto Soudal team. He gets to work with the results of the Dexa scan and draws up nutrition schemes according to the rider's profile."
Lean body mass
“A second important value is the lean body mass, meaning the active tissue in the body. This parameter gives us a nice overview of the muscle quantity in the body. That way, for example, the impact of strength training can be evaluated. This is also a valuable parameter in terms of rehabilitation. Since the scan also shows us possible left-right differences, the rehabilitation of an injury located on one specific side of the body can also be closely monitored. Nutrition schemes used to be drawn up by means of body weight, but now this is mainly done based on the lean body mass”, continues Wim Van Hoolst.
Bone mass and bone density
“The final important value is the bone mass and bone density, a parameter that shows us the strength of the bones. Cycling – except for the crashes of course – is a sport in which the bones are subjected to minimal stress. This means that riders with fragile bones and little muscle tissue around the bones have a much higher risk of fractures in the event of a crash. That is why riders with a rather low bone density are recommended to do more strength training, alternative sports or take supplements”, concludes Wim Van Hoolst.