Much like omega 6-fatty acids, carbohydrates and their main regulatory hormone, insulin, are not inherently deleterious to human health. Many of the problems we see with them come from their gross over representation in the modern Western diet. So, while for most people the journey toward achieving their health goals will entail periods of carbohydrate monitoring and/or restriction, there may also come a time where carbohydrate re-introduction may prove useful. This strategy applies across several levels of health and performance.
Although chronically elevated glucose and insulin levels have been shown to be one of the main drivers of disease, fat accumulation, and metabolic dysfunction in our society, once we take steps to reset the hormonal environment in our bodies and up-regulate fat burning via carbohydrate restriction, we can begin to strategically re-introduce carbohydrates. Insulin is a major hormone in the body and operates in conjunction with many other hormones and processes in the body. Some of the pathways insulin interacts with are involved in muscle building, sleep, fat burning, and thyroid function. After an initial period of carbohydrate restriction or ketogenic adaptation, periodic insulin spikes through carbohydrate feedings can help to rebalance some of these hormonal processes. This helps to keep muscles growing and fat burning.
Individuals who are looking to emphasize fat loss may see better results from less frequent carb feedings, occurring from around once a week to once every ten days. This protocol is intended to optimize hormone levels for sustainable, long-term fat burning. Carbohydrate feedings are best done at night to allow for maximal fat burning throughout the day, and should consist of a 3-6 hour window of carb centered, higher glycemic meals. These meals should emphasize carbohydrates over protein and fat. This protocol is called Carb Night. Frequency and timing of carb night can vary from person to person depending on how the body is responding, convenience, training schedule, social events etc.
Adding a high intensity strength training session prior to carb feedings is a potent catalyst for muscle growth. The training stimulus, combined with a post workout carbohydrate load, enhances the metabolic response of fat burning and muscle protein synthesis. Post workout, the glucose in the blood from carbohydrates will be favorably deposited into insulin sensitive muscle tissue to replenish glycogen stores. Here, through nutrient timing, we are able to advantage of insulin and carbohydrates and use them to fuel and prioritize muscle growth rather than fat growth.
Individuals who are already lean or wish to focus more on performance, recovery, and muscle growth can take greater advantage of the anabolic properties of insulin and carbohydrates by introducing more frequent carb feedings. By utilizing carbs post workout, through some of the processes described above, trainees can experience increased lean body growth and enhanced recovery potential with little to no fat gain. In this scenario, carb feedings are usually implemented 2-4 nights a week, post workout. Before training, and on non-training days, low carb dieting protocols are followed. This is called Carb Backloading.
Endurance athletes may want to follow a strict low carb / ketogenic protocol for an extended period of time (weeks to months), to develop a fat adapted energy metabolism, and then do a few days of heavy carb loading before an event.
All of these strategies are examples of cyclical ketogenic dieting. The “cycle” refers to the rotating periods of high fat and high carb eating, with the majority of the time being spent in the high fat / low carb ketogenic state. This diet model encourages metabolic flexibility and maximal body composition results while also offering convenience, variety, and the performance benefits of multiple fuel sources.