Q. “What do you recommend for a pre-workout meal?”

A small quantity of complex carbs, simple carbs, and protein, such as a carrot and some tofu, or an apple and some cheese (soy, rice, or dairy). Many people do not need a snack right before their workout and actually feel best exercising on an empty stomach. If this is the case, it's wise to have a small snack right away after your workout in order to bring your blood sugar back up, and replace some of the glycogen in your muscles. People who work out hard and then don't eat something afterwards risk getting a headache, becoming irritable, or feeling so famished that they overeat at their next meal.

Q. “When do you think is the best time to workout?”

There is no best time for everybody. I encourage my clients to workout when they feel like it. Their schedule and their natural biorhythms dictate when exercise will feel the best. When people try to exercise at a time that doesn't jive with their natural clock or their daily routine, it feels awful. Moreover, calories burned are calories burned, no matter what time of day you work out. Your body doesn't care when the calories are burned off, so long as you are burning up sufficient calories most days of the week to balance the calories you are eating.

Q. A few years ago, a college student of mine once asked me after Wellness class, “How come all of a sudden in the twentieth century, man has to lift weights? Who decided that this is necessary? Nobody was doing this thousands of years ago.”

He was challenging me and also was frustrated at anything that required structure and compliance. My answer to his question was simple: “Show me a caveman who drove to work in an automobile, sat at a desk all day, and ordered up a plate-full of saturated fat, salt, and sugar at McDonald’s, and I’ll show you a caveman who desperately needed to lift weights.” As long as people spend the majority of their waking hours standing and sitting still, their muscles atrophy (waste away) more and more each year of their adult lives. Cavemen moved vigorously all day, digging, running, climbing, hiking, and lifting heavy objects. Their weightlifting routines were built into their day! Not so these days. If you don’t do caveman activities daily, you need to lift weights.

Q: “I heard that to lose fat, it’s better to run fast and slow intervals rather than just run at medium speed the whole time because the body is kind of like a car— it uses up more fuel when you keep changing speed. Is this true? ” — M. S., in Chicago

You will burn up more fuel by doing an interval workout of alternating fast and medium speeds, but it’s not simply because you keep changing your speed— it’s because you are spending more of the workout time running at a higher speed, which burns more calories than does a medium speed. Calories burned are directly correlated with intensity of exercise. The higher the intensity of work, the higher your heart rate, and the more calories you burn. If you do two workouts of equal duration, but the first one is at a medium speed the whole time and the second one consists of alternating periods of fast and medium speeds, the second workout will certainly burn more fuel because it required more work. However, if you follow the interval format every time you work out, you will eventually find yourself in a state of burnout. High intensity workouts cannot be done effectively day after day without paying a price.

Q: “I’m trying to lose body fat. How can I figure out how much of each food category (protein, carbs, fat) to eat when I’m preparing or ordering food?” — Marc S., in Nevada

First of all, it’s a good idea to use a salad plate, which is smaller, rather than a dinner plate. This will automatically help reduce your caloric intake. Next, picture your plate as a peace sign divided into thirds. One third should be protein, i.e., tofu, beans or lentils, nuts and seeds, or (if you eat animal products) low-fat meats and fish, dairy, or eggs. Another third should be vegetables or fruit. Choose several types of vegetables and/or fruits at each meal and go for bright colors to ensure as many nutrients as possible, the more colorful, the better— red, yellow, orange, and green. The final third of your plate should contain whole grains and starches like barley, wild rice, quinoa, millet, sweet potatoes, or whole wheat pasta.

Q: “I had a tuna melt sandwich at Whole Foods Market today. Was that a good or a bad choice? ” — S. G., in Chicago

Well, let’s pick it apart, one component at a time. First, the tuna— the concern I have for you is the high level of mercury in tuna, a large predator fish. Tuna is notorious for its mercury levels causing serious health problems in those who consume it on a regular basis (once or more per week). If I myself were a meat eater, I wouldn’t partake in it. Next, let’s consider the mayonnaise, which delis tend to use liberally. That’s a whopping amount of saturated fat and calories that isn’t really necessary to make the sandwich taste better. We could improve this sandwich by putting a very small amount of mayo into the tuna, or use a vegan mayo that is made of canola oil (no trans fats!), or not use any mayo at all. Whole Foods Market is so conscientious about promoting vegan alternatives to dairy and eggs that the deli staff probably has some healthier mayo alternative available for those who ask for it. Or, you could forego the mayo altogether since the cheese melted on top is so rich and gives the same gooey, fatty feeling in the mouth as mayonnaise does. I think it’s overkill to use both the mayo and the cheese, which is likely a full-fat cheese. Speaking of cheese, you could request a reduced fat cheese or a soy cheese, which are just as tasty on a sandwich that has several components in it, and this step also will save you a lot of calories. Now, let’s consider the bread. S. G. told me it was white sour dough bread, so I suggested that he ask for a hearty, whole grain bread next time, which will provide lots more vitamins, minerals, and fiber than the white stuff will. White bread contains calories but negligible nutrients while truly whole grain bread is tastier, has more texture, and is more nutritious. Next, let’s talk about the portion size of the sandwich. When I asked S. G. how big the sandwich was, he held his hands apart ten inches or so. That’s a big sandwich. I suggested eating half of it, and taking the remainder home for dinner. Finally, I asked him if the sandwich had any vegetables in it. He said it did not. How about asking the sandwich maker to put some lettuce and tomato on that tuna melt so you can get two types of vegetables into your daily intake? Remember— always strive to eat eight to ten different types of fruits and vegetables each day! So, we turned a large, high fat mayo and cheese tuna melt on white bread into a healthier and tastier version by cutting the portion in half, reducing, replacing, or omitting the mayo, replacing the type of cheese used, adding lettuce and tomato, and putting it on a nitty gritty whole grain bread. Now that’s what I call turning a “not so good” choice” into a “darned good” choice, S. G.!