Diet and fitness trends come in all shapes and forms.  And Fasting is one that has been around for a while as there is extensive research and data on the benefits of Intermittent Fasting.  Cleveland Clinic’s Wellness Institute, among many others, promotes Intermittent Fasting for weight loss but also says it can have a “Beneficial impact on patients with diabetes and cardiovascular disease, help reduce cholesterol levels in certain conditions, affect the process of inflammation and even trigger stem cell regeneration“.  See Full Article Here

The benefits to weight loss and weight management with fasting while without exercise are hard to ignore, but what is the impact of adding exercise?

Cardio Fasting

Cardio fasting has been considered to be “secret weapon” to rapid fat loss for quite some time.  Fitness enthusiasts and trainers alike have touted the impact of cardio fasting, specifically anaerobic exercise, on weight and fat loss.  What is Cardio Fasting?  Cardiovascular exercise performed in anaerobically, which requires stored fuel vs oxygen to perform, in absence of food for fuel storage of 8-10 hours.

The basic idea behind cardio on an empty stomach is that your body will be more likely to use its own fat stores for fuel instead of the food you just ate. This idea, however, is quite simplified and somewhat misleading. Cardio Fasting may help you tap into excess fat in storage more quickly, resulting in more fat loss, but the theory is more complex.

This theory looks good on paper–Food provides fuel for energy, so if there’s nothing available in your stomach, it makes sense that your body would tap into its stored energy—mainly fat—to power exercise. What people don’t know is that the store it seems to go after stored Protein first. AKA your hard-earned muscle lean mass. According to research published in the 2011 Strength and Conditioning Journal, author Brad Schoenfield, Predisent of Global Fitness Services, summarizes the evidence, “Does not support the efficacy of training early in the morning on an empty stomach as a tactic to reduce body fat. At best, the net effect on fat loss associated with such an approach will be no better than training after meal consumption, and quite possibly, it would produce inferior results.”

Read the full article by Brad Schoenfield

VOLUME 33 | NUMBER 1 | FEBRUARY 201124
Cardio After an Overnight Fast

 

Furthermore, the studies have shown that fasted cardio did not burn fat but instead impacted the intensity of your workout. And since workout intensity directly affects how many calories you burn, not eating before a long and intense session could reduce the energy you have to train with and lead to less fat burn and weight loss overall!

 

So, if you are looking to build muscle mass through strength training, it is not recommended that you fast at all before your workout.  Fasting before a strength session (aerobic vs anaerobic workout) can impact your growth aspect because your body may need tap into lean muscle mass (protein) for fueling not just the workout, more important, the recovery from the workout.

In addition, if you are sport-specific training, your performance will be impacted by fasting.  If you goals are performance related, it is important to train with the same proper nutrition and fuel you would require for game day.

So to answer the question about eating before a work out, the answer seems clear.  It is better to be fueled and ready to fire up than not fed and feeling fried!  And, I am sure you are now asking, “What then is the best thing to eat before a work out”?  Or, If you are one who cannot eat prior to exercise due to time constraints or just plain digestion issues, “What Can I do to stop this loss of protein and maximize performance/calorie  burn”?  You ask it and I write about it– Check out the article “BCAA- What are they and why do I need them?” and stay tuned for my next article, “Fuel Up for Fitness”!