As a fueling system, many endurance athletes find that, once they switch to Keto or LCHF (high-fat, low-carb), they are able to consume less during endurance workouts and competitions. When I’m on a High-Carb protocol, particularly right before a workout, I have to continue to stoke my system with carb-rich foods or my blood sugar starts to plummet. However, I don’t face this issue when I’m consuming fewer carbs daily. For this very reason, I find that my body works best when I alternate between periods of strict Keto and the more mild LCHF, which keeps me in mild ketosis. For periods when I want greater mental clarity and energy (Think a more realistic version of Bradley Cooper in “Limitless”), as well as a quick trim down, I lean harder into Keto. When I’m maintaining and still want to keep inflammation low, I’ll gravitate more towards a light LCHF protocol. That said, I also have friends who are much leaner than I am, and if they stay in prolonged periods of ketosis, they end up leaning out too much, which can increase recovery time and have a negative effect on hormones. This is what I mean by there not being a one-size fits all approach!
While it’s pretty widely accepted that Keto works quite well for HIIT training, it seems that we are going to continue to see more and more exploration of the Ketogenic diet for endurance athletes as well. In cycling, my preferred endurance sport, I’ve watched year-by-year over the past ten years as more and more Pro cycling teams shift towards a LCHF/Keto protocol for their athletes. This means they are eating less on the bike, recovering more quickly, and reducing inflammation markers.
In general, the conventional wisdom of yesteryear that dictated “carb-loading” and then stoking the furnace as we work out (think plates of pasta the night before a bike race, followed by a steady stream of syrupy goop throughout the race) is slowly being upended. Can you work out hard and long on a HCLF diet? Yes. And if you’re burning 5-10k KJ in a workout, you’ll still be in a caloric deficit, but at what cost? The inflammation that comes with a high-carb diet increases recovery time, and the ongoing metabolic stress can have long term negative effects on our health. Ever hear of the skinny-fat marathon runner that drops dead of a heart attack? Or know of an older endurance athlete who is not overweight, but depends on statins to maintain healthy cholesterol numbers? More often than not, the common culprit is years of following the LFHC protocol of the Standard American Diet (SAD).
Adhering to a LCHF diet is pretty easy, and there are tons of resources available to keep it interesting in the kitchen. When it comes to strict Keto, though, a lot of folks can get tripped up. I like to think of it as a tool to use during specific periods, and I’ve found that the more I’ve done Keto, the easier it becomes for me to dip in quickly and without the negative initial side effects. When I’m following a strict Keto plan, I tend to create a very basic meal plan and stick to it. I check my fasting glucose and fasting ketones first thing in the morning, and I adjust my macros accordingly. A sample day looks like this: