How Undereating Could Be Destroying Your Fitness Goals

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Are you experiencing the dreaded “fitness plateau”?

You’re working hard at the gym and trying to consistently eat cleaner – so, what’s going wrong?

The problem could be undereating.

You’ve heard it sensationalized as “starvation mode” or read other articles debunk it as a nutrition myth. Here’s what you need to know about the realities of “starvation mode,” and how undereating could be destroying your fitness goals.

So… Is “Starvation Mode” a Real Thing?

The short answer is: yes. However, beware, as the health world has drastically sensationalized it, inflating its symptoms and frequency.

What we know as “starvation mode” is actually adaptive thermogenesis – the body’s evolutionary response that slows metabolism and stores more energy than normal for survival.

This only happens after prolonged calorie restriction. Your body pumps the metabolic breaks to slow down non-exercise calorie burn and converts more calories into fat.

What is non-exercise calorie burn? Good question:

Calories are burned in four different ways:

  1. Base burn: scientifically known as “basal metabolic rate,” this is the energy your body uses for vital function: breathing, blood flow, brain activity etc.
  2. Digestive burn: the calories your body burns in order to digest calories. Score.
  3. Exercise burn: calories burned during exercise.
  4. Non-exercise burn: calories burned when moving (but not explicitly working out), such as fidgeting, strolling, toe tapping, whatever.

Common Myths of “Undereating”

  • Adaptive thermogenesis does not slow metabolism enough to completely stall weight loss. (It does.)
  • It will not make you gain weight. (It will.)
  • Adaptive thermogenesis slows non-exercise caloric burn, but the other metabolic rates remain relatively stable during this time. (They don’t.)

What Does Adaptive Thermogenesis Feel Like?

If you’re trying to lose weight by slashing calories and doing tons of cardio, you’re at risk of plateauing. Your body slows down non-exercise burn (#4 above), so that you’re burning fewer calories while at rest.

It also dramatically undermines your efforts to stay on the diet bandwagon. Expect to experience the following symptoms:

  • Intense food cravings
  • Risk of binging
  • Irritability
  • Lack of energy / motivation
  • Brain fog / lack of focus
  • Lower cognitive function
  • Lower memory retention
  • Depressed sex drive
  • Plateau in weight loss

As your body weight decreases, so does your caloric burn – but this is normal. That’s why you should readjust as you’re losing weight, or you’ll eventually plateau.
-Jay of A Workout Routine  (on Twitter: @aworkoutroutine)

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How to Prevent the Plateau: Eat More.

If you’re at risk of an adaptive thermogenesis plateau, you need to EAT. And you’ve got to eat WELL.

Try Fasting, Not Starving

If you’re plateauing, your metabolism might need a boost.

Small periods of fasting do not engage “starvation mode” (adaptive thermogenesis) – because you’re only restricting your calorie intake for 24 hours at most. If you’re experiencing a slower metabolism or a plateau in weight loss because you’re undereating, then, paradoxically, fasting could help you in your situation.

Learn about the benefits of intermittent fasting.

As Martin Berkhan of LeanGains explains, short-term fasting actually increases metabolic rate (caloric burn), rather than suppressing it. Evolutionarily, it makes sense:

“Epinephrine and norepinephrine (adrenaline/ noradrenaline) sharpens the mind and makes us want to move around. These are desirable traits that encouraged us to seek for food, or for the hunter to kill his prey, increasing survival. Thus, our metabolic rate is increased in short-term fasting (up to 60 hours).”

Martin Berkhan (on Twitter: @Martinberkhan)

Bottom Line

Don’t starve yourself. Prolonged calorie restriction weakens your body and your mind, making you cranky, unfocused, and more likely to binge-eat.

If you’re experiencing a fitness plateau, satisfy your appetite with nutritious whole foods (go crazy with those crudités). Try shaking up your fitness routine with a HIIT workout, and surprise your metabolism by trying some intermittent fasting.

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