Eating After Exercise

The question “What should I be eating post-training sessions?” pops up frequently in the context of athletes and weekend warriors alike.  The answer lies in the type of exercise you’ve just performed, since different fuelling systems require different nutrient ‘refills’.

Firstly, you need to understand that any form of exercise increases or enhances insulin sensitivity.  Let me explain the relevance of this effect.  When you eat a meal that has carbs in it (fruits, vegetables or grains), the pancreas will be stimulated to produce insulin.  Insulin is the hormone that ‘collects’ glucose (the end result of the breakdown of carbs) from the bloodstream and takes it to the cells, in effect, looking for a place to store this sugar.  Enhanced insulin sensitivity means that it’s easier for your body to take up sugar from your bloodstream into tissues like muscles, where it can be stored or used as fuel.

Under normal circumstances, the cells should be receptive to this insulin signal (the signal to open up and let glucose in) and should respond appropriately.  However, if the diet contains high amounts of carbs (in particular, processed carbs like bread, pasta, white rice, biscuits, pastries, sugary drinks, energy bars etc.), more insulin is required to collect the larger amounts of sugar from the blood.  Over time, with this pattern of higher insulin levels, the cells become ‘deaf’ to the signal and thus need more and more insulin in order to recognise, or hear, the signal.  This is what’s called insulin resistance, or impaired insulin sensitivity, and is a hallmark of Type II diabetes, as well as being a major risk factor for other chronic diseases.

Being insulin sensitive is important because elevated insulin levels are one of the primary drivers for high blood pressure, high cholesterol, diabetes and weight gain.

Now, going back to the fact that exercise enhances insulin sensitivity, it’s important to note that this is particularly true when the post-workout/training meal is low in carbs.  After a training session, the body will be nitrogen-poor and certain muscle tissue will have been broken down.  This leads to the need for replenishment with both amino acids (proteins) and vegetable/fruit-type carbs.

Let’s say you’ve just completed a cardio session.  Ideally, you’ll want to wait 45-60 minutes, in order to ride the calorie-burning wave that comes with the workout (i.e. the temporary increase in metabolic rate).  Don’t wait longer than 60 minutes as this shifts the body into ‘starvation’ mode, tending to store rather than burn.  Keep this meal or snack a low starchy-carb one (e.g. above-ground vegetables or salads or low-fructose fruits like passion fruit, apricots, plums, cantaloupe, raspberries), and include some protein (what kind will depend entirely on your metabolic type).

On the other hand, let’s assume you’ve just finished a weight-training session.  Due to the nature of the muscle breakdown and the energy system used, you’ll want your food to be quickly absorbed, so eat within 15-30 minutes post-workout.  This meal or snack should be high in both protein (the redder and darker animal proteins are higher in amino acids) and more starchy carbs, e.g. a banana (containing high potassium levels, which appears to help with recovery).  Other starchy veg-type carbs include below-ground vegetables or squashes.

I’ll mention metabolic typing again, since understanding your own unique biochemical fuel needs is (in my opinion) the most performance and health –enhancing tool you can use.  If you’re a person who requires more densely–packed amino acids, due to the fact that you tend to oxidise (burn) your carbs too quickly, then good quality red meats, organ meats and dark poultry meats are going to be your best amino acid replacement.  If you oxidise slowly, the lighter proteins will be better for you.  Likewise, if you’re an MT that utilises sugars well, your carb choices will be different from an MT that doesn’t handle it well.  Each metabolic type requires a unique mix of carbs, proteins and fats at each meal, as well as very specific types of nutrients.  Once you establish and eat to your metabolic type, you’ll be working with your biochemistry, instead of against it, leading to improved health, weight, performance, energy and immunity.