What to Eat After Cardio by Chris Aceto
Just what are you supposed to eat after a hard cardio session? While a lot of people know a high carbohydrate protein shake is the way to go after weight training, few really know the best things to consume after aerobics – a workout generally intended for fat burning. Of course, there are people out there who do cardio "to be heart-healthy," but let’s face it, the overwhelming majority hit the treadmill or stair stepper because it helps keep body fat at bay. By focusing on your post-cardio meal, you’ll be able to maximize fat burning and keep the torch lit even after your cardio session.
To decide what to eat after cardio, you have to approach the meal with the understanding that the types and quantities of food you eat affect your hormone levels. These hormones play a direct role in the burning (or not burning) of body fat. Keeping fat-burning hormones elevated – the very hormones that increase during cardio – is the single most important factor in determining what is best to eat after a cardio session. OK, let’s start with the simple stuff.
We know it makes no sense to eat a lot of fat after cardio. If your knowledge of physiology is limited, you can rely on common sense. It’s simply not a rational idea to chow down on a lot of dietary fat after having just jumped off the treadmill. Truth be told, dietary fat is easily stored as body fat, more so than protein and carbohydrates.
Protein is anti-catabolic. Dietary amino acids derived from protein foods can be used directly as fuel after cardio. Often, protein stores are broken down with cardio. That is, in addition to burning body fat, longer cardio sessions or cardio sessions performed in a total calorie deficit can cause a loss or burning of your hard-earned muscle. Since protein protects against muscle loss, taking in easy-to-absorb protein following the cardio session is a must. It can put an end to protein breakdown and keep the metabolism from taking a dive. That’s because burning protein is a strictly catabolic event, and catabolism is always associated with a slower metabolic rate.
Carbs are the double-edged sword of nutrition. You need them for recovery and growth, yet they can initiate fat storage. Carbohydrates promote a rise of insulin, and insulin can be classified as a fat-storing hormone. In general, the more carbs you eat, the more insulin is released. Insulin is the quarterback of the entire fat-storing team and regulates the signals that allow fat cells to "open up" and store more body fat. Simultaneously, insulin directs dietary fat into fat cells and drives carbohydrates down fat-storing pathways. Does it make sense to eat a lot of carbohydrates after cardio? Not really. When you eat a lot of carbohydrates, insulin levels will increase, shutting down fat-burning hormones and enzymes released during cardio.
The two benefits to cardio are 1. it burns calories, and 2. it changes the hormonal status in the body, favoring the burning of body fat. Your carb quantity and choice after cardio affects the hormonal balance. Where cardio increases the circulation of catecholamines, tiny messengers that target fat cells to break them down, insulin decreases the release of catecholamines.
Whereas cardio increases the output of hormone sensitive lipase (HSL), a hormone that "opens" fat cells and allows fatty acids to be stripped as fuel, insulin opposes its release and can even spike levels of lipoprotein lipase (LPL), which does the exact opposite of HSL. LPL seals off fat cells and helps push fuel into fat stores. Therefore, it seems best to avoid carbohydrates after cardio to keep the fat-burning hormones elevated.
However, small amounts of insulin actually support the metabolism. How so? Insulin is also anabolic. It stimulates growth and repair of muscles. And, during a recovery or growth state, the body literally steals from its fat stores to obtain energy in order to sustain the recovery or growth process. Growth and recovery require fuel (energy), and most of that energy will come from fat stores. Insulin also supports the uptake of thyroid hormones, calorie-burning hormones, by tissues. So, with regard to carbs after cardio:
1) A large amount will shut down fat burning and reverse the hormonal advantage associated with cardio.
2) Skipping carbs altogether leaves you with "just protein." While protein helps prevent a loss in muscle, your body always needs a small amount of carbs for support.
3) A small amount of carbs helps support recovery and growth without shutting off the fat-burning process.
4) Small amounts of carbs coupled with protein can prevent thyroid hormones from declining.
I think the best bet to go is to consume 25 to 40 grams of fast-acting protein, such as whey protein, egg whites or fish, along with 30 to 50 grams of carbohydrates within 30 minutes of cardio. Ideally, the carbohydrates ought to be fiber-based, such as oatmeal, oat bran, peas or corn. Fiber slows the breakdown of carbohydrates, allowing them to be delivered in an almost "time-released" fashion. The benefit: slower-digesting carbohydrates result in moderate insulin rises, and moderate insulin is our goal. Moderate insulin offers anabolic or building support, without reversing the fat-burning state induced with cardio. Simple carbs, such as white bread, juices or high glycemic carbs, should be avoided because they tend to spike insulin levels, and the resulting spike can compromise fat burning by suppressing fat-burning hormones and enzymes.