Episode 123 – Calorie Cycling

Key Topics Covered

Calorie cycling sounds like a technical nutritional term, however, it is just the concept of consuming a different amount of calories on different days.

Calorie Cycling Types and Logic

1. Calorie deficit 5-6 days per week and either maintenance calories or a surplus as a refeed / cheat meal/day to try to improve fat loss – we will explore this further.
2. Different calories on different days based on training needs. Example: more calories on training days and fewer calories on rest days.
3. Different calories on certain days for food flexibility. Example: Calorie deficit 5 days of the week and then 2 days of higher calories on the weekend.

Are There Direct Advantages for Fat Loss?

Theoretical Perspective

• Fat loss will largely come down to calories in and calories out. A calorie deficit is required for losing overall weight in the form of fat and/or muscle.  
• The second variable is muscle e.g. if a deficit sets you up for fat loss, but one version of you held onto more muscle, theoretically, they are also losing more fat than a version that is also losing more muscle.  
• For calorie cycling to help fat loss, it would need to either 1) Reduce calories in or increase calories out OR 2) Help muscle retention.
• For the sake of this part – we are assuming weekly calorie intake is stable, so that isn’t a factor here.  
• Theoretically then – if calorie cycling was going to help, it would have to help by increasing the calories out portion e.g. “speeding up your metabolism”.
• This is the concept behind cheat meals.

Research Outcomes

• The research on that topic has not been promising. This is because the impact is too acute. 
• While we see spikes in certain hormones that make it seem like a refeed or cheat day is increasing calorie expenditure, when you look at things from a longer timeframe, there is no noticeable difference. 

Are There Direct Advantages for Performance and Muscle Growth/Retention?

• Theoretically, you could time your intake to align with certain training sessions.
  • For example, if one day you had a rest day, but another you had a 2-hour lower body session in the gym, adding more carbs on that day before the session could lead to a better training session.
  • Subsequently, the improved performance in that session can lead to greater performance over time.
  • This logic can also apply to other things like endurance performance. 
  • This may also prevent you from being in a large surplus on rest days if your training volume is typically quite high. 

Drawbacks of This logic

1. This makes an assumption that improved performance = improved training stimulus (and therefore, long-term outcomes).

• Example: Let’s say you do all sets to an RPE 8.  
• One version of you has more glycogen, the other has less.  
• The version with less glycogen gets less reps and less volume throughout the session. But do they gain less muscle and strength? We need to look at the actual outcomes over time.

2. Everything is a tradeoff.

• By having more calories prior to that session, you are having less elsewhere.  
• You are still recovering on non-training days so adequate nutrition is needed.
• Therefore, are you potentially trading improved performance for reduced recovery?  

3. We don’t actually have research showing that this approach leads to better muscle and strength gains. 

• It’s just theoretical that this could help. And it makes sense that it may help more under extreme circumstances with very high training volumes. For example, ironman athletes.
• A simple way I’d typically implement this is just by adding more food pre-workout in a lot of cases, that isn’t consumed on rest days.  

Food Flexibility 

• You can use calorie cycling to allow you to be more flexible with food while still achieving the same results. 
• This could be for weekends, or any day such as a mid-week event for example. 
• For example: Eating 50 fewer calories 6 days per week gives you 300 calories extra one day. Double that to 100 fewer and it gives 600 extra. 
• Where this falls apart is if taken to an extreme. 
• If you ate 1000+ extra calories over 2 days on the weekend – suddenly you have to drop so many calories during the week that you are now likely: Hungry, underfuelled for training, and also consuming fewer micronutrients overall. 
• It’s also worth acknowledging that this often reduces overall dietary quality too. This is because more micronutrient-rich foods are often restricted during the week to make room for other foods on the weekend that typically are less micronutrient-rich. 

Indirect Benefits 

• The food flexibility approach can make things easier to stick to for certain people. There can be mental benefits to it. 
• The approach of adding fuel on training days can also help improve how you feel. This is difficult to quantify easily in research.
• For example, in the research, participants are forced to train near to failure. However, in reality, you are not under these circumstances.
• Therefore, you may be more likely to push yourself if you are feeling better because of the additional fuel.

Summary

There are certainly some benefits that come alongside calorie cycling, particularly if it’s not taken to an extreme.

It can provide more food flexibility, and if you personally feel better and can train harder because of it, that is worth something too.

Relevant Links / Resources

Blog Posts

• Is Carbohydrate Cycling Good for Fat Loss?
• Are Refeeds or Cheat Meals Beneficial for Fat Loss?

Relevant Studies

• 2 Day per Week Refeed Study
• 24hr Hormone Response to Changes in Intake
• Intermittent Energy Restriction (Focus on Low-Calorie Days)
• Intermittent Energy Restriction in Athletes (Focus on Refeeds / Cheat Meals)