Creatine and Carb Loading During Endurance Events
Most of us associate creatine with its ability to improve performance in burst like sports with a lot of explosiveness (think match sprints or football), but what role can creatine play in endurance events like longer road races?
The scientific community has long established the ergogenic role of creatine in explosive and burst like sports such as sprinting and intermittent sports like soccer, hockey and football. Creatine's research dates back to the early 90's and since then hundreds of studies have consistently shown creatine's ability to improve high intensity exercise (creatine has other potential benefits related to the brain and bone, however I'll save that for another post). What do we know about a sprint or high intensity effort at the end of a 120km cycling event? Does creatine play a role in longer endurance events that include late or mid race intensity?
Researchers at the Australian Catholic University wanted to investigate this question and put together a study including 18 athletes, cyclists and triathletes; fit but not professionals. The cyclists did three performance trials of 120km, which included alternating 1km and 4km high intensity efforts at every 10km mark, followed by an 8% climb (done indoors on a cycling treadmill), at 90% of VO2max, until exhaustion. For performance trials 2 and 3, Subjects were split into 2 groups, creatine loaded or placebo. Each group consumed either 6g/kg or 12g/kg of body weight of carbohydrates, plus creatine intake of 20g for the first 5 days followed by creatine at 3g for 9 days, or placebo. Subjects followed a crossover design for the carbohydrate protocols. During the performances, athletes also consumed 60g carbohydrates hourly in the form of a sports drink or gels.
Although the 1km and 4km efforts were not significantly different between groups within the 120km, nor was the overall time for the 120km performance trial different, both the creatine plus carbohydrate groups significantly increased their maximal aerobic power in the last 4km sprint to the finish. This has important practical implications for road races that come down to a sprint finish.The placebo plus carbohydrate load group (12g/kg/bw) also improved maximal aerobic power above baseline in the final 1 min sprint.
Also of note, the creatine plus load group achieved higher muscle glycogen compared to all other groups, however there was no performance effect noticed between the two carbohydrate groups, even with higher glycogen in the load group. The researchers note in the discussion that this could be due to the fact that subjects were also consuming 60g/carbohydrates per hour during the test. Basically, consuming 6g/kg/bw carbohydrate intake plus 60g/hour during the trial, subjects were able to perform as well as those consuming 12g/kg/bw and 60g/hour during the trial. Perhaps had there been no in trial nutrition this would have differed, but that would no reflect how an elite athlete would fuel during a 120km cycling event (although some athletes certainly do under eat during races, so it's possible the load may have helped this type of athlete). There is existing evidence that creatine consumed with carbohydrates can improve glycogen storage and this is certainly something for athletes to keep in mind when considering creatine intake as an ergogenic aid for endurance type sports.
Cyclists are concerned with power to weight ratios and the researchers kept this in mind when designing the trial. The creatine group did add pre-peformance body mass versus placebo, but it appears the effect was negated by improvements in power during the 8% climb to exhaustion. There were no significant differences between the placebo and creatine groups during this portion of the study. Replicating results like this could give endurance athletes peace of mind as far as the cost benefit of putting on a few pounds of body mass, knowing the gains in power will at least negate that gain when the road goes up.I'm hoping to see more research in this area.
You can imagine how difficult it would be to try to mimic a 120km road race, and I can understand why the researchers went with this style of protocol. Not a simple layout for subjects to execute. Perhaps a Zwift set up could be an interesting platform to use for future research, as it's an indoor platform that athletes are starting to take more seriously (I just read there is a legit Zwift World Championships in the making!) and could be familiar with. If you could set up a course where athletes are following a protocol while also racing one another, that would be interesting. Of course the athletes would have to forget tactics for the day as the study would have specific design parameters to be met. Still, there is a good chance the motivation factor would be high if subjects could also see others up on the screen, which could mimic a real race scenario as best as possible. These platforms could make lab research a bit more field like.
Evidence here concludes that creatine could be beneficial at the end of an endurance event for a sprint finish. Any competitor knows that this could be the difference between winning or losing. The way I look at is, if you can have more power for all of your shorter efforts in training and you can bump up your overall power and strength by using creatine, without being penalized for gaining some lean body mass, it's going to be a win win.
As always with new nutrition or supplements (of the very few supplements that have been proven to improve performance), if you want to use creatine yourself, you'll want to experiment with it during training to see how you feel and respond to it and then make a decision based on your experience and data. Your diet, genes and of course your training, will all play a part in how ,much creatine impacts your strength and performance.
**Note: Always source a product that has been third party tested by a company such as nsf.com and ask for batch test results. If a company isn't willing to be completely transparent about their product, deal with another company. Taking supplements always comes with a risk and the responsibility lies with the athlete in the end. Do your due diligence on any products you choose to consume.
Keep the rubber side down and stay tuned for some tips on transitioning into the off season!