New Years Resolutions 101: What to Eat for Working Out

It's not even the end of January, hopefully you haven't given up on your New Year's resolutions yet!

With many people aiming to get healthy, start exercising, and lose weight in the new year, the gyms have been packed and, with this weather, the trails have been filled. The basics are pretty simple: be active and eat a variety of fresh healthy foods. But, sports nutrition can seem a lot more complicated if you're new to it.

Here are some rules of thumb to follow as you aim to stay healthy and fit even after January:

Fuel yourself for exercise

"To start a workout you need to be fueled so that the workout is productive," says Sunny Blende, M.S., sports nutritionist in Sausalito.

If you're not fueled, then your body has to break down muscle in order to get enough energy. No big deal, you think, I don't want to be all muscle anyway. But, you know what muscle is? It's lean and it's not fat. If your body is breaking down muscle, then you won't be able to get and stay healthy.

Being fueled beforehand can be as simple as eating a healthy meal three to four hours before you want to run or hit the gym. Then, a quick snack or sports drink right before will get you ready to go.

For the early risers, who workout before making it to the office, that often means eating something very light before heading out -- like toast with a little peanut butter -- or, if you can't eat right before working out because it upsets your stomach, then it's best to eat something nutritious and full of fiber the night before, so it'll be digested while you sleep. (Dessert doesn't count!)

The general rule, says Blende, is that the closer you get to the exercise then the more you'll want to rely on liquids and easily digested sugars, from sports drinks or simple snacks. But, if you want to lose weight, then you don't want to eat too much sugar, which means you'll need to plan ahead: eat more nutritious meals earlier, so you have time to digest before hitting the gym.

Stay hydrated

Drinking water throughout the day is always a good idea, whether or not you're also working out. Most people don't drink enough water, relying instead on sodas and juices. But, when you plan on adding some exercise and activity, then you need to be extra sure that you're staying hydrated. It used to be that sports nutritionist would say that by the time you were thirsty, you were already dehydrated. But, that led to people drinking way, way too much water -- gallons to hydrate their 30 minute easy jogs. With so many people doing marathons or running races for the first time and drinking water as if they were running world record times, overhydration became a dangerous problem in the last few years. Overhydrating can cause hyponatremia, a condition where the sodium levels in your blood drop dangerously low, and can ultimately lead to kidney failure, nausea and even death.

Now, sports nutritionist simply advise people to drink when they're thirsty and not to overdo it. "Drink to your thirst," says Blende.

It's also possible to measure your sweat rate. Simply weigh yourself (without clothes), workout for an hour drinking as you see fit, then weigh yourself again. If you lost one pound, then that's 16 ounces of fluid. Add to that however many ounces you drank. (For example, if you lost two pounds -- which would be a lot -- and drank 10 ounces of water, then you lose 42 ounces of sweat per hour.) That can help you ensure that you drink the appropriate amount during your exercise.

What you eat during a workout comes down to duration and intensity

Our bodies only absorb about 200-250 calories/hour, depending. That means that no matter how much we shovel into our mouths while working out, we'll only absorb a set amount. Most people can get through anything shorter than an hour without needing to eat during their workout. But, once you're going for an hour to an hour-and-a-half or more at about 60-65% (or some moderate level), then you'll deplete your carbohydrate stores, says Blende.

"It comes down to duration and intensity," she said.

At low levels of intensity, Blende said, your body burns fat first. But, fat is a slower fuel source, so when you go harder and/or longer, your body has to burn the carbs. That carb tank can then be depleted and needs to be refilled -- depending on what you're doing.

If you plan to workout for an extended period of time or at a high intensity, then you'll want to consume about 200-250 calories/hour and about 50-60 grams of carbohydrate/hour. It's generally considered a good idea to vary the source (at a molecular level) as well.

If you're new to working out, then sports bars and sports drinks can be a "learning tool," says Blende. They typically make things simple -- using basic carbs and sugars, without much fiber, to get you through the workout. But, if you don't like them, then you can always have real food -- bagels or bananas. Dave Scott, the famous Ironman triathlon world champion, used to eat figs while riding his bike. It's also possible to make your own sports drinks out of basic water, salt, and maltodextrin.

Eat protein and carbs right after a workout -- but not too much

Immediately after you exercise, you have an unique opportunity. If you've tapped your stores, which takes more than a short workout, then you can rebuild them. And, during the 30 to 60 minute window right after exercise, what you eat "double-stores in your muscles when it would normally go to fat cells," said Blende.

It's one of the few times you can direct calories to where you want them to go.

To do that, eat about 200-250 calories in that 30 minute window at a ratio of about 1:3 protein to carbs. If you only eat protein, which some people do, thinking they'll build muscle, "it's like trying to build a house with wood and nails, but the carpenters didn't show up," said Blende. You want to digest the food within an hour of finishing activity, so the longer you wait, the more you need to take in simple sugar to digest quickly.

That, however, doesn't mean you should go nuts. Lots of people will do moderate exercise, feel good about themselves, and then eat way more than they burned.

"Lots of us underestimate our calories and overestimate our exercise," said Blende. Was that spinning class really an hour of working out or was it 40 minutes and some stretching and some talking and getting your shoes on and fixing your bike?