When We Cause Metabolic Damage and How to Fix It

Competitors and Mainstream Exercisers are Struggling

 Whether you are a competitor struggling to shed that last layer of fat or fitness enthusiast working hard but not losing weight, the answer could be as simple as your food intake and exercise.  The human body is a smart machine and knows what you are up to when calories become restricted and energy output is increasing.  Slowed metabolism is a huge issue with bodybuilding competitors but is now hitting the mainstream exerciser as well.  Let’s break down the scenario of what happens when drastic measures are taken for weight and fat loss.

How Metabolic Damage Begins

runner taking a break in forest
Peter Muller/Cultura/Getty Images

 Let’s say you have put on a bit of fat and are anxious to shed it for either an upcoming fitness competition or even to get into that summer bikini.  Your determination is strong and “I can do it” attitude has taken over all reasoning of just how the fat is going to fall off and quickly.  You start with aggressive cuts to caloric intake consuming only half of what you are used to eating.  As a man that could mean instead of eating 3000 calories per day, now you are raking in a measly 1600.  The same holds true for a woman eating 2200 calories per day and shaving it down to 1200.  On top of that, this man and woman add an hour of cardio per day to their already exhausting exercise program.  Guess what, both have lost several pounds over the first few weeks and happy fitness dancing is happening until the “big stall”.  

What the Heck Happened?

Slowed Metabolism
Fat Loss Frustration Sets in When Metabolism Slows Down. Paul Bradbury OJO Images/Getty Images

 Fat has stopped shedding, the scale is not budging and pure frustration has now set in.  Both the man and woman apply even more drastic measures by cutting out all carbs in their diet and decide to also reduce fat intake to 25 grams per day (that’s only 2 handfuls of nuts).  The body responds to the adjustment but barely shedding any fat weight this time.   Continued disappointment in their strategy sends them to the gym adding once again an extra hour of cardio since they can no longer make changes to their already restricted diet.  A few more weeks show nothing in fat loss and the body has stopped responding to their efforts altogether.  What the heck happened?

The Metabolic Meltdown

Slowed Metabolism
Restricting Calories is a Sure Way to Sabatoge Metabolism. Peter Dazeley The Image Bank/Getty Images

 The body said “enough” is what happened.  The man and woman created a metabolic meltdown by causing a drastic slowing of their metabolism through excessive caloric restriction, cardio and stress on the body.  For some reason, metabolic damage seems to affect women more than men and some people throw in the towel and give up at this point, while others push through with even more severe restrictive and body abusive exercise behaviors.  What can I do?

Understanding Metabolism

Slowed Metabolism
The Human Body is a Surviving Machine. Oliver Burston Ikon Images/Getty Images

 Understanding the body better and how to implement safe fat loss strategies is the first place to start.  The body is a surviving machine and adapts quite well to what we do to it.  Any restrictive diet will start slowing down our metabolism which is a normal response.  Additionally, many people are unaware that eating food causes a lowered energy output because calories are being burned during the digestive process.  A cascade of events happens when the body senses fat loss and struggles to stay in balance (homeostasis).  Thyroid levels decrease and reduce nervous system output attempting to stop further weight loss.  Once the additional calorie cuts and cardio entered the picture to reduce more body fat, guess what, a further drop in thyroid levels and lowered nervous system function.  Because the body is undergoing continued stress of extreme caloric restriction and additional exercise, it further adapts by increasing cortisol and reducing testosterone.  The end result is loss of muscle and holding of whatever fat is left to cling to.  Both the man and woman put their bodies through a damaging metabolic process which is no fault of their body.  The body is simply fighting for survival and will do what it takes to make that happen.  You make a change and the body will respond with an adjustment and that is how it works.  Taken to extreme causes an ugly downward metabolic spiral until it shuts down altogether.  Is there a better way to lose fat and protect my metabolism?

What Can I Do?

Slowed Metabolism
Protect Your Metabolism While Losing Fat. shapecharge E+/Getty Images

 Taking on a different “mental game” to fat loss will help and being patient with your progress.  Fat loss is not to be rushed and aiming for approximately 1 to no more than 2lbs per week is a healthy goal.  This will reduce risk of muscle loss and allow your body to adjust slowly to applied changes.   Begin by making minor changes to your caloric intake, keeping carbs in your diet and not overdoing cardio sessions.  For every change or move you make, your body will respond with an adaption similar to playing a chess game.  For example, cutting calories does not need to be combined with adding extra cardio all at once.  Your body will not be your friend if you do too much too soon and will surely put you in “check mate”.  Give it a chance to get used to reduced calories without the added stress of increased physical exercise.  Carbs are also essential to keeping metabolism elevated by activating a fat-burning hormone (leptin) which helps with your energy output.  Reducing and eliminating them lowers leptin levels so it will be important to maintain carbs to some degree throughout your fat loss program.  Similarly, fat intake is important for hormones to function right in your body, especially testosterone.  If fat intake is severely reduced your body will adapt by holding onto any fat stores for survival.  Your body knows when it is being starved and will fight you all the way. 


The takeaway for a healthy metabolism while losing fat:

*Be patient – 1 to no more than 2lbs of fat loss per week.

*Apply one change at a time and allow your body to adapt.

*Carbs are essential for an elevated metabolism.  They may be reduced but not eliminated.

*Fat intake is important for hormone function (testosterone) and burning fat.  Moderate amounts of fat will prevent starvation cues and promote metabolic function.

*If leaning for a competition, apply the same methods in reverse to put healthy weight back on, but don’t pack it on.

*Maintain a healthy weight on and off competitive season and the same goes for mainstream exercisers and this will keep your metabolism running like a clock. 

*Did I say be patient?  Remember your body knows what you are doing.   Avoid metabolism “check mate”.



Journal of the International Society of Sports Nutrition, Metabolic adaptation to weight loss: implications for the athlete, Trexler et al., 2014

Experimental Biology and Medicine, Peripheral Signals Conveying Metabolic Information to the Brain: Short-Term and Long-Term Regulation of Food Intake and Energy Homeostasis, Peter J. Havel, 12/01

American Journal of Physiology, Low-fat diet alters intramuscular substrates and reduces lipolysis and fat oxidation during exercise, Edward F. Coyle et al., 3/1/01

International Journal of Nutrition, Food Restriction, Performance, Psychological State and Lipid Values in Judo Athletes, E. Filaire et al., 12/15/00

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