The Art and Science of Low Carbohydrate Performance by Volek and Phinney. It has been really eye-opening. It shouldn't be. I lost 60#s years ago while following Atkins for about 2 years. I got down to 124#s from a high non-pregnant weight of 185#s (and pushing a size 16 on my just shy of 5'4" frame). Then I fell off the wagon and regained 20. I started running almost 7 years ago in the hopes that I could re-lose the weight without "dieting." FAIL. I am now 30#s over my low weight and halfway back to my heaviest starting point.
For years I have struggled with how to go back to eating a low-carb/ketogenic diet AND engage in my favorite activities -- running and cycling. I fell victim to the aerobic-exercise-requires-carbs myth. A few times I tried cutting my carbs down to a "moderate" level of 100-150 net/day, but could never run or bike for more than about 45 minutes before bonking. And the insane hunger with even that many carbs in my system. That has been the biggest challenge any time I have tried to cut calories. Atkins was like a dream come true for me. I lost weight without crazy hunger and felt healthier than ever, even on a caloric deficit.
I'm only about a third of the way through the aforementioned book, but reading it has given me a big DUH moment! If I'm not actually in ketosis and I cut back on carbs, then my body has no clue what to do once my limited glycogen stores are depleted. BUT if I don't let my body run on glycogen from the outset, then it has no choice but to power itself on fat stores. This was true before I became an endurance athlete and did weight workouts. It's still true.
Both of the authors come from athletic backgrounds and demonstrate the effectiveness of low-carb for non-sedentary, aerobically active individuals (people like ME) -- a population that hasn't really been well-addressed previously.
I found a great interview with Dr. Phinney, MD, PhD. I like that he discusses the Human populations that thrive on keto diets and have exceptionally active lifestyles, including the Inuit and Maasai.:
Dr. Peter Attia, MD's The Eating Academy website has also been really enlightening. He dropped about the same amount of weight that I am hoping to lose while being aerobically active and documents the enormous benefits reaped in fitness and VO2 max testing done before and after adapting to a ketogenic diet.
I still have 2 more cyclocross races this season (so I need to wait to start back up with low-carbing until race season is over, since I will likely have at least two weeks of adaptation away from carb-fueled fitness. During that period I will likely have no choice but to scale back on the effort and duration of my workouts), but starting 12/3 I will be back on the ketosis wagon. I'm really looking forward to it. I will miss beer and wine, but I can't wait to indulge in all of the keto-friendly foods I can eat with gusto, again (my love for bacon and cheese are the stuff of legend). I won't be able to indulge in bread and sugar, but I'll get to make up for that with the things I really love...cheese, nuts, berries, meat, salads...mmmm.... And I won't miss the 20-30#s that I hope to lose in the next year. I would love to be able to set some new race PRs with a lighter body.
And I turn 40 in Feb., so I want to get my weight off before it starts to become an even bigger challenge with middle age.