- Drinking a Protein Shake Before a Workout: Protein is digested more slowly than carbs, so too much pre-workout can give you stomach cramps. Have them afterward instead.
- Exercising on an Empty Stomach: This forces your body to break down its own muscle mass and convert it into blood sugar.
- Overusing Energy Bars: Too many of these and you might "eat back" the calories you burned exercising.
- Not Eating Enough "Good" Fat: The right kinds of fats are needed for your cells to heal and repair post workout.
- Buying Into the Afterburn Myth: You will indeed burn more calories in the hours after a workout -- but for most it amounts to just 50 additional calories burned, not enough for a calorie splurge.
Interestingly, research has also found that exercise-related alterations to gut hormone signals could contribute to the overall effects of exercise and help manage body weight.
Exercise is already known to increase sensitivity to leptin, a hormone released from fat cells that inhibits food intake. A new study also looked at gut hormones that are released before and after a meal to initiate and terminate food intake.
According to Science Daily:
"The authors measured gut hormone release after a palatable tasty meal before and after rats exercised in running wheels. In rats with a lot of running wheel experience, consuming a tasty meal led to increased blood levels of an inhibitory feeding hormone, amylin. After the meal, the same rats showed a more rapid rebound of a stimulatory feeding hormone, ghrelin."
You're probably well aware that the food you eat has an immense impact on your health, but did you know that it also impacts how much benefit you get out of your workouts? What you eat can either add to or take away from your exercise benefits, and if you're devoting the time to workout, you want to know how to harness your meals to support your efforts, not detract from them.
I do agree with some of the tips sports nutritionist Cynthia Sass included in the Shape article above, namely that you need to include healthy fats in your diet and avoid eating too many energy bars. But there is a major food disaster that was not included in this list, which I'll detail below, and I also disagree with her assertion that you should not exercise on an empty stomach, as this, in fact, may be a key to keep your body biologically young.
Why Exercising on an Empty Stomach May be Key
There is plentiful research showing that exercising first thing in the morning may give you added benefits -- even counteracting poor diet and helping with weight loss. One reason for this is likely because when you exercise first thing, it means you're exercising on an empty stomach.
One of the explanations for how exercising on an empty stomach can prevent weight gain and insulin resistance despite overindulgence is that your body's fat burning processes are controlled by your sympathetic nervous system (SNS), and your SNS is activated by exercise and lack of food.
The combination of fasting and exercising maximizes the impact of cellular factors and catalysts (cyclic AMP and AMP Kinases), which force the breakdown of fat and glycogen for energy. This is why training on an empty stomach will effectively force your body to burn fat.
Alternatively, you can try intermittent fasting, which can help you build younger brain and muscle tissue. This calls for you to exercise in late morning or early afternoon and remain fasting (or eating only light raw foods, vegetable juice and/or whey protein or eggs) all day until 30 minutes after your workout. You can include 20 grams of a fast-assimilating protein like a high-quality whey protein concentrate 30 minutes before if you want.
Simply put, exercise and fasting yield acute oxidative stress, which keeps your muscles' mitochondria, neuro-motors and fibers intact. You may have heard of oxidative stress before in a negative light, and when it is chronic it can lead to disease.
But acute oxidative stress, such as occurs due to short intense exercise or periodic fasting, actually benefits your muscle. In fact, as fitness expert Ori Hofmekler shares:
"… it's essential for keeping your muscle machinery tuned. Technically, acute oxidative stress makes your muscle increasingly resilient to oxidative stress; it stimulates glutathione and SOD production in your mitochondria along with increased muscular capacity to utilize energy, generate force and resist fatigue.
Hence, exercise and fasting help counteract all the main determinants of muscle aging. But there is something else about exercise and fasting. When combined, they trigger a mechanism that recycles and rejuvenates your brain and muscle tissues.
Growing evidence indicates that fasting and exercise trigger genes and growth factors, which recycle and rejuvenate your brain and muscle tissues. These growth factors include brain derived neurotropic factor (BDNF) and muscle regulatory factors (MRFs); they signal brain stem cells and muscle satellite cells to convert into new neurons and new muscle cells respectively. Incredibly, BDNF also expresses itself in the neuro-muscular system where it protects neuro-motors from degradation. This means that exercise while fasting signals your body to keep your brain, neuro-motors and muscle fibers biologically young."
If You Can't Exercise on an Empty Stomach …
A number of individual factors can play a role in whether or not fasting before exercise is right for you, such as your age, when you last ate, whether or not you're pregnant, taking medications, your medical history, level of fitness, and the type of workout you engage in. For example, some people feel weak or nauseous while exercising on an empty stomach, and in this case a small meal before exercising may be appropriate. The type of food you choose for that meal is incredibly important, and a muffin or bagel simply won't do. Your body needs a high-quality, fast-assimilating protein.
A recent study published in the journal Medicine and Science in Sports & Exercise demonstrated that consuming whey protein (20g protein / serving) 30 minutes before resistance training boosts your body's metabolism for as much as 24 hours after your workout.
It appears as though the amino acids found in high-quality whey protein activate certain cellular mechanisms (mTORC-1), which in turn promote muscle protein synthesis, boost thyroid, and also protect against declining testosterone levels after exercise.
In practical terms, consuming 20 grams of whey protein before exercise and another serving afterward will most likely yield the double benefit of increasing both fat burning and muscle build-up at the same time. Again, not everyone will need to eat something prior to exercise, but if you do, a high-quality whey protein is one of your best bets. It'll curb your hunger while still optimizing fat burning.
What You Eat After Your Workout is Also Incredibly Important
If you decide to give intermittent fasting a try (and even if you don't), what you eat after your workout is crucial to stop the catabolic process in your muscle and shift the recycling process toward repair and growth. If you fail to feed your muscle at the right time after exercise, the catabolic process will go too far and can potentially damage your muscle.
So you MUST EAT within 30 minutes after your workout, and your meal should include fast-assimilating proteins, such as high-quality whey protein. Personally, I tailor my post-workout meals depending on the type of exercise I've done that day. My favorite post Sprint 8 meal is a Pure Power protein shake without anything added as that would tend to impair the absorption of the fast-assimilating whey proteins.
What Food to Avoid Before, During and After Exercise
To maximize the benefits of exercise, including the weight loss benefits, you'll want to avoid energy drinks, sports drinks, most energy bars and even "healthy" drinks like vitamin water. These and virtually all other processed foods and beverages contain sugar, including fructose, which will sabotage your exercise benefits.
Fructose tricks your body into gaining weight by fooling your metabolism, as it turns off your body's appetite-control system. Fructose does not appropriately stimulate insulin, which in turn does not suppress ghrelin (the "hunger hormone") and doesn't stimulate leptin (the "satiety hormone"), which together result in your eating more and developing insulin resistance.
Fructose also rapidly leads to weight gain and abdominal obesity ("beer belly"), decreased HDL, increased LDL, elevated triglycerides, elevated blood sugar, and high blood pressure -- i.e., classic metabolic syndrome.
Further, you may be aware that one of my top recommended forms of exercise are high-intensity exercises like the Sprint 8 program. Sprint 8 exercises boost your body's natural production of human growth hormone (HGH), which is a vital hormone that is key for physical strength, health and longevity.
"A high sugar meal after working out, or even a recovery drink (containing high sugar) after working out, will stop the benefits of exercise induced HGH. You can work out for hours, then eat a high sugar candy bar or have a high sugar energy drink, and this will shut down the synergistic benefits of HGH."
The reason why restricting sugar and fructose after exercise works is that they will prevent the production of the hormone somatostatin, one of the primary purposes of which is to inhibit the production of human growth hormone.
How Exercise Influences Your Meal Hormones
While we're on the topic of food and exercise, an interesting new study, presented at the 2011 meeting of the Society for the Study of Ingestive Behavior (SSIB), revealed one way that exercise may help control your body weight by altering the hormones released by your gut after a meal.
In rats that exercised, increased levels of an inhibitory feeding hormone, amylin, were released when a meal was eaten, and a more rapid rebound of ghrelin occurred after the meal. Further, exercised rats treated with a gut hormone called CCK, which limits meal size, decreased their food intake more so than sedentary rats.
As one of the study's authors told Science Daily:
"Our new results indicate that the beneficial effects of exercise to control body weight might occur by altering the way in which meals release gut hormones that regulate food intake, and also by changing the sensitivity of individuals to these gut hormone signals."
Exercise is already known to increase sensitivity to leptin, the "satiety hormone" involved in appetite regulation, providing even more reason to make physical activity a regular part of your life.
Two More Important Tips to Optimize Your Workout Results
While exercise is important and crucial for weight loss, about 80 percent of your ability to achieve an ideal body weight will be related to your food choices. So if you've been exercising for some time and are still not losing weight or achieving results, make sure you are:
- Engaging in high-intensity exercises like my Sprint 8 exercises, which engage a certain group of muscle fibers that you cannot engage through aerobic cardio. Engaging these muscle fibers causes a cascade of positive health benefits, including improved fat burning.
- Following the dietary advice available in my comprehensive nutrition plan. I am confident that if you adhere to the recommendations in this plan, you will be able to optimize your weight and your exercise results.