Creatine for Endurance Cyclists: Can you gain an edge?
Most of us associate creatine with either its ability to improve performance in sports with brief intense/repeated sprints, or improve strength and increase muscle mass as a result of resistance training. But what about the role of creatine in endurance events such as road or endurance cycling, where intermediate or finishing sprints occur under aerobic conditions? Can creatine give you an extra edge?
What does the research say?
Creatine + carb loading
Researchers at the Australian Catholic University wanted to investigate this question and put together a study including 18 athletes, including cyclists and triathletes. Participants undertook three cycling performance trials. Each trial was 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 VO2 peak, to mimic a road race. Performance trial 1 served as a baseline. Two days prior to trials 2 and 3, athletes were randomized to consume 6g or 12g (load group) of carbohydrates per kg of body weight. One group supplemented with creatine, 20g for 5 days followed by 3g for 9 days while the other was given a placebo. During all performance trials all athletes consumed 60g carbohydrates hourly in the form of a sports drink or gels while cycling. For trial 3, athletes received the opposite condition as they did in trial 2.
What did they find?
The 1km and 4km efforts were not significantly different between groups, nor was the overall time for the 120km performance trial. However, both the creatine plus carbohydrate groups significantly increased their maximal aerobic power in the last 4km sprint to the finish, and the placebo plus carbohydrate load group (12g/kg/BW) increased maximal aerobic power above baseline during the final 1 minute sprint. This has important practical implications for road races that come down to a sprint finish. At the elite level, everyone is fit, so any edge can make the difference.
Creatine and improved glycogen stores:
Evidence from several studies has shown creatine’s ability to increase muscle glycogen stores, which is presumed to be due to a creatine induced cell volume increase, which can stimulate glycogen synthesis. (Glycogen is stored carbohydrate).
In the study we are discussing here, the creatine plus load group (12g/kg/BW carbohydrates) achieved higher muscle glycogen compared to all other groups, although this did not result in improved performance between the two carbohydrate groups. The researchers note that this could be due to the fact that subjects were also consuming 60g/carbohydrates per hour during the test. Essentially, by consuming 6g/kg/BW carbohydrate intake plus 60g/hour during the trial, participants 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 (60g/hour during the cycling trials), this would have differed, but that would not reflect how most elite athletes would fuel during a 120km cycling event. Some athletes will under fuel during races, so it’s possible the load could have helped an athlete with inadequate carbohydrate intake based on what we know about the ergogenic effects of carbohydrate intake on endurance cycling. You can read more about creatine’s ability to increase glycogen storage here, and we will circle back to this topic in the next study.
Power to weight ratio:
Cyclists are often concerned with power to weight ratios, since long races often include elevation. In my experience it’s the reason many cyclists shy away from supplementing with creatine at all. Researchers kept this in mind when designing this trial, which is why they added the 8% finishing climb after the 120km TT. It turns out the creatine group did add pre performance body mass, versus the placebo group, 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. If a cyclist was confident that their weight gain would be negated by power gains for hilly races and they were confident they could maximize their fueling strategy by increasing glycogen stores with creatine, supplementing would probably seem like an advantageous decision. But as always, athletes need to weigh the pros and cons of supplementation based on the context of their sport and their individual situation.
Creatine vs no creatine during 60 minute aerobic cycling with sprints:
A few other quality studies have shown creatine supplementation can improve intermediate sprints under aerobic conditions. This study investigated a lower dose of creatine supplementation 6g/day for 5 days, vs no creatine supplementation within the same group of athletes.
Participants had to do repeated top power intervals within a 60 minute cycling bout, laid out as follows: After 30 minutes cycling at a specific aerobic wattage based on prior testing, they were asked to execute two sets of 10x 15 second intervals at 7.5w/kg with 45 seconds rest in between each interval. Between sets of ten, participants returned to their aerobic pace for 120 seconds, and then attempted to repeat ten more 15 second intervals. They were asked to follow this with 30 additional minutes of aerobic cycling at the same pre determined pace they started at. They did this protocol before creatine supplementation and then again on the sixth day after creatine supplementation and were unaware of their results on the first test.
During the no creatine supplement protocol, participants were not able to perform all twenty of the 15 second high intensity intervals, however after creatine supplementation the number of high intensity intervals completed increased significantly. There were no significant differences in the two thirty minute aerobic portions of the protocol, although those who were unable to complete the second 30 minute portion at the prescribed pace before creatine supplementation, were able to maintain this pace for 4 minutes longer after creatine supplementation.
More on glycogen:
Another important finding was the response of blood sugar to exercise between trials. In the pre creatine supplementation trial, blood glucose (sugar) levels dropped significantly between baseline and 25 and 50 minutes, however in the creatine supplement trial no significant decreases in blood glucose were measured. Again this brings us back to the finding that creatine can increase muscle glycogen storage, which is an important consideration for endurance athletes to consider, based on the high carbohydrate demands of elite endurance competition.
Finishing Thoughts:
Improving intermediate and finishing sprint performances under aerobic conditions during cycling could be the difference between making the break or winning the sprint or wearing the green sprinters jersey. My perspective is, if you can increase power during your shorter efforts in training and bump up your overall power and strength for race day through creatine supplementation, without being penalized for gaining some lean body mass, it’s a win win. Although there aren’t a ton of studies in this area, the quality of the existing research is high. Hopefully we’ll see more studies to back the existing literature in the coming years.
Always test supplements during training first:
As always with new nutrition or supplements, if you’re planning to supplement with creatine yourself, you’ll want to experiment with it during training to see if and how you feel and respond on it and then make a decision based on your own experience and data. Your diet, genes and of course your training, will all play a part in the magnitude that creatine impacts your strength and performance. There are non responders, but that could be because you already have a high creatine diet, in which case more isn’t making a significant difference.
Supplement safety:
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, power through the pedals and keep moving forward.
For more information on creatine in endurance cycling see the references below.
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