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This article compliments my colleagues’ two articles regarding the performance considerations of what e-racing requires and the ethical and conduct considerations as we enter this new sport. Read Virtual eRacing: Let’s Talk About Weight Cutting and Performance Improvement and Pitfalls in Weight Cutting for Virtual eRacing.

Cycling is adding a new discipline of racing in the form of e-racing. E-racing can be done on various platforms including (Zwift, RGT, Rouvy, Bkool, and FulGaz). Racers are required to have a bicycle and a stationary trainer with a power meter. At the high level of e-racing, racers are required to have a smart trainer which connects to the platform which changes the resistance of the bicycle/trainer as the terrain of the virtual course changes. When the course goes up hill, the resistance gets harder. As part of this virtual racing, racers are required to document their body weight into the platform. Each platform has their own equations for calculating the speed the racers go in relation to their watts per kilogram body weight (w/kg). As Adam explained, typically the easier way to manipulate your w/kg is to change your body weight (kg). Riders can expect to gain up to 5% in their power each year with dedicated and structured training, but changing your body weight by 5% can much easier. Group rides and most virtual racing does not require a certified or ‘official’ weigh in. All that is required is that you input a number. At the higher level, organizations and companies organizing e-races require weigh-ins in the form of racers taking a video of them weighing themselves on a scale that has been calibrated using a standardized weight (such as a dumbbell or a kettle bell). Currently there is no standard for when these weigh ins occur for e-racing in relation to the race. 

With weigh-ins becoming part of the sport, we are now forced to approach the topic of weight manipulation and strategies such as cutting weight and weight loss more than we have in the past. Whether athletes perform weight cuts (short term weight loss by dehydration and loss of water weight) or choose to lose body weight longer term (in the form of fat or lean mass) to favor their watts/kg ratio, coaches and athletes should be aware of the benefits and risks associated with these methods.

3 considerations for manipulating your weight in order to perform in e-racing

How often you are performing weigh-ins.

The more often an athlete needs to complete weigh-ins, the less opportunity the athlete has for short-term weight loss as an option. If there are only a few days or weeks between weigh-ins this will require the athlete to be at their lightest, within their performance requirements, on a regular basis rather than for infrequent competition. Simply, the frequency of weigh-ins determines the level at which athletes can safely manipulate their weight or whether they should manipulate it at all.

How much weight you can lose without performance losses.

Ultimately, the goal of any race is to win. In order to win, athletes need to be at their best performance on the day of the race. In order to do this the athlete will need to produce their highest watts possible, in addition to race tactics. Manipulating the kg side of the watts/kg should not come at the expense of the watts side. Performance losses can be seen with short term mistakes such as not fueling well with calories, electrolytes, or fluid before the event and long term mistakes such as chronically underfueling manifesting in issues such as Relative Energy Deficiency Syndrome (RED-S). RED-S leads to a cascade of physiological complications that affect health and performance such as low glycogen levels, low red blood cell count, increased incidence of bone fracture and more. 

Each athlete will have their own personal threshold for performance with regards to body weight. Many athletes will perform better at a higher weight even if they are physically able to lose more. 

  • Short Term weight loss, or weight cutting: Studies show that athletes start to see performance losses between 2.5-8.0% below their euhydrated state. Being euhydrated means their body’s cells have an ideal amount of fluid available. For athletes considering performing a short term weight cut, determining how and how much weight to lose for a weigh-in needs to consider the level of performance losses and safety associated with that water weight loss. Dehydration symptoms include lethargy, dizziness, nausea, confusion and irritability. Complications of prolonged dehydration include heart injury, urinary and kidney problems, seizures and low blood volume shock. So this means that even if your kg portion of the equation is favorable it must not be at the risk of these potential side effects for both your performance and your health.
  • Long Term weight loss, losing fat and/or muscle mass For athletes considering losing fat and/or lean mass for longer term weight loss, athletes should consult a Registered Dietitian to determine a safe and effective weight as well as a plan to obtain that weight. As mentioned earlier, the quest to lose weight can have its own complications (RED-S) in addition to what happens at the end if the athlete becomes too low body fat or lacks the appropriate muscle mass. Athletes who are too low body fat may experience low energy, loss of performance, heart issues, hormonal imbalance, loss of menstrual cycle, gastrointestinal problems, a weak immune system and more. Clinically speaking, essential body fat for females is 10-13% and males is 2-5% body fat. Each athlete has their own threshold for body fat percentage and performance, but these values are clinically within a range where practitioners would expect to see complications.

How much time is between the weigh-in and your race.

Sports which require weigh-ins typically have a standard amount of time between weigh-in and competition. For sports like jiu-jitsu the weigh-in is typically no more than 3 hours before a fight and so performing a weight cut is irrelevant because there is no time to regain fluid from a cut in order to perform at the athlete’s best. Sports such as MMA may be up to 36 hours before a fight and so athletes have much more time to regain fluid weight from a short term weight cut before a competition.

Cycling e-racing does not have a standardized time for weigh-ins. Some races allow racers to perform weigh-ins up to a week in advance but then also require weigh-ins day of. The athlete’s weight the day of the race must be within a certain percentage of the week before weight. Ultimately, there must be enough time between the weigh-in and the race to be optimally hydrated and fueled for best performance. The body can only absorb so much fluid and calories per hour and therefore the time an athlete has to regain fluid is critical to their performance. If there is not time to regain weight from short term weight loss, the weight cut becomes irrelevant as the performance, or w side of the w/kg equation, may decline. 

Ultimately racers and coaches should know the short term and long term risks of weight cutting, low body fat percentage, low muscle mass and underfueling to achieve low body weight. 

Be sure to sign up for my upcoming webinar on Weight Cutting for Cycling E-Racing.

About the author: Kristen Arnold MS, RDN, CSSD is a level 2 USA Cycling coach as well as a Registered Dietitian (RD) specializing in sports nutrition and is a board Certified Specialist in Sports Dietetics (CSSD). With Kristen’s nutrition expertise and diverse experience in the sport of cycling as a racer and a mentor, she provides a comprehensive approach to her coaching. She works with athletes from the beginner to elite ranks in road, cyclocross, and mountain biking disciplines. Kristen is professional road racer racing with ButcherBox Pro Cycling, and seasoned mountain bike and cyclocross racer. Learn more about Kristen.