Ketogenic Diet – Part 1

Does the ketogenic diet have a place in the triathlon world?  I’m on a search to find out.  The other week my wife and I started following a ketogenic diet.  Bacon, eggs, avocados, butter, coconut oil – where do I sign up?  If by now you haven’t heard of the keto diet or don’t know what it entails there is plenty of information out there for you to consume, which is not the purpose of this particular blog.

One thing I found when researching is there isn’t a ton of information out there on how this diet works out for triathletes so my goal is to document and share my personal experience with it.  With that said, there are a number of factors you should consider before starting this diet for yourself.  Talk to your doctor, talk to your coach, or feel free to shoot me a message as well.


To start things off let’s talk about why I’m starting this little experiment.  In 2016 I completed my first Ironman and leading up to that I was following a pretty strict diet of what most would consider a low carb/high fat diet but nothing that comes close to falling under the keto category.  But what I found during this time was that my body became very efficient at using fat for fuel.  For example, I wouldn’t have any problem going out for my weekly 2 hour long run with absolutely zero nutrition.  Carrying this ability into my Ironman was something that I feel contributed to my success on that day (apart from the GI issues I experienced on my run).  I am just starting my Ironman build again and so I wanted to get my body back to the point where it is able to utilize fat as a primary fuel source.  My intent is not to follow the keto diet all the way up to the point of my Ironman, however follow it strictly for at least a month or two and then slowly starting incorporating (healthy) carbs back into my diet leading up to the race.  If things go as planned I think it will translate nicely on race day. 

Over the next couple of weeks I’ll share with you the details of my diet, training, energy levels, and other aspects of my life, so with that said let’s get into some of the details of the first week of doing keto.


My goal is to get 65% of my calories from fat, 30% from protein, and 5% from carbs.  Typically you’ll see recommendations of 20-25% for protein however given my training workload I wanted to increase this slightly and make sure I was facilitating recovery for my body.  At the end of the day I found was consuming anywhere from 30 to 40 grams of carbs per day, with net carbs ending up anywhere between 20 to 30.  An average day looked something like this: cup of coffee w/ coconut oil, eggs, bacon, avocados, fatty meats, some cheese, some nuts, small amounts of vegetables, and because I’ve got a sweet tooth my wife and I discovered some keto friendly desserts as well.  One of the biggest things I noticed during the first week was it was actually challenging to eat over 2000 calories a day following this approach.  For the most part this was just because I wasn’t feeling as hungry throughout the day.  And generally speaking I didn’t find it too difficult to make this dietary switch during the first couple of days, although around day 3 I had a large craving for sugar, and carbs in general, but nothing that was too overwhelming.  I also noticed that I wasn’t having to eat as much food for dinner and the smaller portions kept me satisfied.  Generally speaking, I’m usually pretty hungry at the end of the night after I get done with my training so this was a bit of surprise to me to see that not be the case.  In summary, actually eating all the right food wasn’t a problem and I generally enjoyed what I was able to eat throughout the day.


I knew I was going to have to adjust my effort levels while getting accustomed to this diet and I was expecting to have lower energy levels each day as a result of my body not having much glycogen to burn during exercise.  Below is what the training week looked like (also note that this week had a high focus on running which was something planned out prior to starting the diet):

-Monday: Swim and Strength training

-Tuesday: Bike and Run

-Wednesday: Swim, Strength Training, and Run

-Thursday: Bike and Run

-Friday: Swim, Strength Training, and Run

-Saturday: Long ride with Brick Run

-Sunday: Long Run and Swim

At the end of the week it came out to be just shy of 16 hours of training, with the higher intensity sessions falling on Tuesday, Wednesday and Friday.  Even though these were higher intensity, specifically I had fartlek runs and hill repeats on these days with very strong efforts, I kept everything relative to how my body was feeling for that day; meaning I didn’t concern myself with my pace and to a degree my heart rate, and instead listened to my body kept my effort levels aligned with how my body was feeling for that particular session.  At this point, I know what my body should feel like when I’m supposed to go hard, easy, and points in between (which is one of the reasons I’m a big fan of training off of effort and not get too caught up in metrics).  So for example, on Tuesday I had a fartlek run consisting of a 10 min warmup, with a main set of 15x1 min very fast efforts with a 1 min easy in between, followed by a 10 min cool down.  On a normal day my 1 min efforts will be around 5min/mile pace (+/- a few seconds).  This week running at 6min/mile pace gave me the same perceived effort level as the 5min/mile pace so that’s what I did.  I didn’t force my body to give me something that it wasn’t able to knowing that I needed to be smart with my training. 

I won’t get into the specifics of each session but here are my general observations.  I found my body getting fatigued pretty quickly during my swims and I never really felt strong in the water all week.  I could still put in the distance during the sets however there was a noticeable difference in how my body felt after swimming more than 100 yards at a time.  As a result I took the opportunity to focus on staying smooth in the water paying extra attention to my form.  Both bikes were aerobic rides done at a moderate pace and neither presented a big challenge.  Since I was keeping my effort levels lower and not tapping into my glycogen reserves my body handled these without any real issues.  The runs throughout the week were the toughest of all the sessions.  I felt tired and generally just pretty poor due to the increased effort levels but again kept things toned down and just wanted to execute as best as possible on each session.  Saturday’s long ride was 4 hours and my intent going into this session was to keep the power dialed way back (I’m talking avg power of 150 watts for the ride) and see how the body did with it’s first long endurance session.  All in all, I felt fine and to my surprise, I felt pretty good getting off the bike for my 30 minute brick run, although effort again was dialed way back compared to what I’d normally do.  I took the same approach for my long run on Sunday.  Kept it very dialed back around 10min/mile pace and found I had a fairly good energy level during this session. 


My energy levels outside of training felt as if they showed an improvement.  I didn’t drink as much coffee throughout the day and the biggest thing I noticed is that I personally struggled to fall asleep at night due to feeling “awake” later than I’m accustomed.  Usually around 10pm I’m ready to hit the pillow and pass out however, I wasn’t falling asleep until on average about 11pm throughout the week.  As a side effect, I was waking up feeling more tired as usual which made it more challenging to complete my morning training each day.  Energy levels during training, as mentioned above, suffered s expected but I feel like I was able to manage that appropriately during each of the sessions.


I knew this was going to be a challenging week with a lot of unfamiliar things coming my way.  Again, my focus was on taking things one day at a time and keeping everything in check based on how my body was feeling.  By the end of the week my body had begun producing a “moderate” amount of ketones (according to my urinalysis sticks) so it was moving in the right direction but I hadn’t reached full ketosis.  With that said, let me go grab another piece of bacon and I’ll check back in with you guys next week!

If you guys have any questions/comments in the meantime I’d love to hear from you.  Leave a message below or shoot me a message through my website and I’ll get back to you.

Happy training.


Travis Vance3 Comments