Written by Astrid Naranjo (Clean Health Accredited Clinical Dietitian)
The human body isn’t a big fan of dieting. Evolution has taught the body that when calories are restricted, there is food scarcity. So, for the human body it means that it needs to decrease energy expenditure and become more efficient in what it does in order to survive.
This makes a lot of sense back when food was scarce and our ancestors were those early humans who were able to evolve this metabolic adaptation to limited food, so they didn’t starve to death. Unfortunately, the human metabolism hasn’t had enough time to unlearn the millions of years of evolution that came before it.
Despite this, all is not lost! Most times it is thought of the term ‘periodization’ when it comes to training, however, nutrition interventions can also be periodized. Just like it may be useful to change up training, nutrition strategies need to be changed/adjusted at times to elicit the desired response or to mitigate negative adaptation to energy restriction during a fat loss phase. Sometimes this is done mostly for psychological reasons, sometimes this is done for physiological reasons and sometimes for a bit of both. Obviously, the nutrition strategies and interventions should match your client’s evolving goals, rate of fat loss, physical activity levels, etc.
You may have heard about refeeds and diet breaks before, it is actually a trendy topic at the moment and more research has been coming out in recent years…. Until recently, there wasn’t much research available on the long-term effects of refeeds and diet breaks. Some studies in the early 2000s showed transitory increases in leptin in response to acute overfeeding, however, most of the guidelines around refeeds and diet breaks were based on anecdotal experience. In the last few years, some recent studies looking at the long-term effects of refeeding and diet breaks have helped shed some light on this topic.
Well, these tools can be very handy in terms of teaching or letting the body know to not being so worried about being in a calorie deficit. However, these tools should be used strategically based on your client’s personal circumstances.
We cover the topics of diet breaks and refeeds in our online courses, the Science of Nutrition & Training the Physique Athlete. Click here to enrol!
Refeeds may be helpful to offset muscle loss and delay the onset of negative metabolic adaptation in the short term. However, it is likely that over time, your client will still encounter some muscle loss and negative metabolic adaptations, especially the longer they remain in a deficit.
This is where diet breaks come in. A diet break is a planned break from being in a calorie deficit. It’s usually used to break up a longer dieting period and typically lasts a week or two (or longer if needed), returning to eating at maintenance. In other words, these are periods of time at higher calories that can signal to the body that your metabolism doesn’t need to adapt negatively, because there is some food available.
Here are a few reasons to implement a diet break:
- Psychological break from caloric restriction
- Alleviate some of the water retention issues associated with prolonged periods of fat loss
- Help bring recovery in from the weight room back up to speed
- Teaches the client that there is a time and place to “grind”
- Improve weight loss efficiency by offsetting some of the negative metabolic adaptations
However there’s a few important things to consider when programming a diet break:
- Not everyone is going to want to implement diet breaks in their fat loss program. Some people actually need to get into a diet rhythm and stay there, and breaking up that rhythm may make them more stressed and reduce adherence. There’s no point trying to force someone like this to change their macros every 2 weeks just because the MATADOR study says they’ll lose more weight. If getting out of the groove is going to put adherence at risk, then you’re better off sticking to continuous restriction. Without adherence it doesn’t matter if you use refeeds or diet breaks, or whatever, you’re not going to get results the results you want for your client.
- Diet break does not mean free rein to eat whatever your client wants. You gotta emphasize this to your client: it’s a break from the deficit, not a break from their main goal or from being a bodybuilder or caring about what they eat. A properly implemented diet break involves raising calories to your client’s estimated maintenance level… No more, no less. Of course, we can’t estimate your maintenance requirements with absolute precision, so you’ll inevitably miss a bit high or low, but the goal is to be as accurate as possible.
How to program a diet break:
Programming diet breaks is relatively simple. Once you decide to implement a diet break, think about how much time is sufficient? Is your client willing to do a longer fat loss phase?
For general weight loss that is intended to be permanent, a two-week at maintenance could be very doable, and the results from the MATADOR study implementing this technique are quite strong. Now, there’s no strict rule here, and it will really depend on each client’s circumstances.
For example, a bodybuilder that is ahead of schedule, or willing to dedicate to a more prolonged contest prep period, could probably commit to a one-week break implemented every 3-4 weeks, or implemented as needed. If your client is an early-career bodybuilder with plenty of room to grow before they reach their genetic potential for muscularity, they may be able to consider how much time of the year they could spend cutting. A gen pop client, may benefit well from occasional diet breaks, although frequency of these will really depend on body composition and leanness.
Longer diet breaks tend to be more protective of the metabolism. However, the more days spent in a diet break, the longer your client will spend in the fat loss phase. For example, you could say, well, “I’m just gonna diet break every other week. ” Okay, well you’ve still got to have a week of deficit, but it’s gonna take you longer to lose that 10 kilos of fat or whatever you want it to lose when you’re doing every other week at maintenance calories or more. Whereas if you just dieted straight through, you would get it off faster, albeit you may incur more metabolic adaptation, and you may lose more lean body mass. So the trade-off to sparing lean body mass and less metabolic adaptation is that the overall time for you to lose body fat is longer.
Diet breaks aren’t magic, so they don’t come without a cost. We always have to take the extra calories from those days into account in terms of our weekly calorie budget.
For example, let’s say you wanted to implement a 3:1 diet break schedule with your client.
If for example, the goal deficit to get to their target goal weight has been calculated for a total of 16 weeks. So if we added in diet breaks we need to introduce periods of 1 week at maintenance after every 3 weeks of deficit. This will add 4 weeks worth of breaks to your clients fat loss phase.
What about the calories? Every time you are to go into a diet break, you may want to update your client’s current TDEE and get them to that maintenance calories. This is an important step since TDEE will potentially go down each period because body weight is dropping and weight is a big factor in determining TDEE.
When calculating macros, make sure the increments come mostly from carbs and fats. Since calorie intake is being temporarily increased, there is no need to increase protein. Higher amounts of protein are need only when your client is in a deficit. If anything, you can reduce your protein slightly on a diet break to give more room to carbs and fats.
Diet break mistakes:
There are a few things that are often done incorrectly with diet breaks.
- Eating too much during the diet break.
Your client should aim to maintain weight during a diet break – a slight increase or decrease is fine since there will be shifts in fluid. Reducing diet stress can cause a drop in water retained under the skin, meaning your client may look leaner and lose some weight. On the other hand, having more carbs available will potentially mean more glycogen storage in muscle tissue, making you look a bit bigger and weigh a bit more.
- Drastically altering the foods your client normally eats.
A great way to achieve a bloated physique and larger laundry loads is to eat a ton of foods your client is not used to having. A better way to go about it is to mostly eat the same, just larger portions.
- Using diet breaks too often.
It’s normal to feel hungry and more fatigued when dieting. It’s normal and unavoidable that your client will experience metabolic adaptation when losing weight. It doesn’t mean a diet break is needed every 2 weeks. Remember, when at maintenance, your client isn’t going to lose weight. Taking a diet break means you’re extending the length of time it’s going to take to reach your client’s target weight, so it should be used strategically. Often, it’s psychologically easier to just push through and get your client to hit their goals sooner rather than prolong the process.
Diet breaks are just tools. You don’t have to use them. They’re not mandatory. For some situations they may actually be a bad idea, but they can be useful for others.
Focus on what works best for each individual situation. Lifestyle, preference, psychology, all of these things play huge roles. Since your clients aren’t machines, you can’t just plug the same diet break module into every client’s program and expect it to work.
The longer and more frequent the diet breaks, the longer the fat loss phase of your client will be.
For the general client not on a time schedule, the break can occur as needed.
This may be when a life event necessitates it or when the client simply feels that they need a break. Basically, there are no strict scheduling requirements in this situation. There are also times that a diet break could be programmed somewhat intuitively, meaning that there often comes a time in a longer-term diet phase where fatigue, hunger, cravings, etc. start to become a chronic concern (fat loss also often slows down drastically). While subjective, this is a sign that the body is adapting to the diet and this can be a good time to take a diet break. Nonetheless, this should not used as an excuse to take breaks far more frequently than they should.
In contrast, for those on a strict time schedule, the planning of the breaks should be somewhat more systematic. Once the dieting time has been estimated, it is ideal to implement the diet break at relatively even intervals.
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