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Lori KirwanGary Hills

Health Advisor is a regular column where contributors share their knowledge in fields ranging from fitness to psychology, pediatrics to aging. Follow us @Globe_Health.

Yes, spring has definitely sprung at the gym.

Conversations after every class I teach are some form of question regarding, "How to burn that belly fat?" or, "What is a quick way to get ready for that bikini?"

Fat-burning is a metabolic process that occurs when the body is in a caloric deficit. When the body requires more energy than it is consuming, it metabolically has to go to the storage banks (fat cells) to get the energy to function, whether at rest or during activity. No matter how much exercise you do if you eat more than you expend you will not burn fat.

Some dieters make the mistake of going on a low-calorie diet. This may work short-term for rapid weight loss, but what it does in the long term is slow your metabolism down and set you up for major weight gain the moment you start eating normally again. Also, you are probably not getting all the vitamins and minerals you need to be healthy, so you put yourself at risk for illness and feeling tired and sick.

Instead, here's what I'm telling my clients:

1. Read labels. You need to start reading labels and observing the calories per serving, how much a serving is and hidden ingredients that can affect your fat-burning goals. Try to stick to fresh food from the produce section.

2. Calculate how many calories you need. There are numerous metabolic calculators that can help you estimate your resting metabolic rate and help you estimate how much you burn during exercise. The ones that factor in gender, height, weight and activity level can serve as good estimates of resting metabolic rate. In order to burn fat, you need to be about 100 to 200 calories just below the number of calories you burn in a day. If you go too much below that number, your metabolism slows down because the body wants to protect itself from starving.

3. Eat smaller, protein-rich meals spread throughout the day. The body actually burns more calories processing protein than carbs or fat. This cashes in on the "thermic effect" of food, which is the increase in energy expenditure (above your resting metabolic rate) that occurs after eating and as a result of your body digesting and processing nutrients.

4. Drink more water. Increase water intake to at least nine to 10 tall glasses per day. This helps improve overall bodily function and will also help make you feel more full.

5. Understand insulin. When you have glucose in your blood (after you eat carbohydrates), the pancreas is signalled to produce the hormone insulin which takes the glucose in your blood and shuttles it to the body's cells that need it. Extra glucose is stored as glycogen in the liver and in muscles. Once the muscles and liver are full of glycogen, any additional glucose is converted to fat and stored in various places in your body for later use.

6. So, cut out simple carbohydrates. Basically, fast-digesting simple carbs like candy, sweets, rice cakes, white bread, pasta, cereal and even some fruit tend to spike insulin. Fat-burning will only occur when insulin is not present in the bloodstream.

7. Choose slow-digesting carbs. Foods such as steel cut oatmeal, sweet potato and legumes have a low glycemic index, so they don't cause as much insulin to be secreted. Avoid processed foods and eat as many leafy greens as possible.

8. Time your carbs. We need the good carbs for energy, vitamins, minerals and fibre, but for optimal fat-burning you need to be strategic as to when you eat them. First thing in the morning and before or right after you exercise are safer times, because the glucose will be used to replenish liver or muscle glycogen rather than stored as fat. Try not to eat any carbs as part of or after your dinner – leaving them out will set your body up to burn fat while you sleep.

9. Develop muscle. A lot of my participants who want to burn fat participate in high-intensity cardio classes to try to burn as many calories as possible. Yes, you will burn calories during cardio classes. But don't forget that your muscles are your metabolic tissue. By increasing lean body mass, you will increase your resting metabolic rate and burn more calories – not just while you are working out, but also at rest and during your sleep. Make lifting weights a regular part of your exercise routine to make your body a fat-burning machine.

10. Stress less. Try to reduce stress in your life, if possible. Emotional stress is linked to emotional eating and consumption of more calories than you can afford if you want to burn fat. In addition, hormones like cortisol, that are secreted in response to stress, slow down or shut down fat metabolism.

11. Get sleep. This is when you build and repair body tissue. In addition, while you are sleeping you are fasting, and the body will burn glycogen stores and fat because there is no insulin circulating. Sleep deprivation can also actually lead to hunger and overeating, or craving carbohydrates. What's more, if you are tired, your workouts are probably not as robust as they could be.

12. Cut out alcohol. Alcohol is a sugar and, as a result, increases insulin secretion – thereby stopping the metabolism of fat. It is particularly disadvantageous to drink alcohol at night – that prime fat-burning time – because your body won't burn fat if there is sugar available in the bloodstream.

Lori Kirwan is a Toronto fitness instructor and trainer with a Ph.D in Exercise Physiology from University of Toronto. In her current work at the Madonna-owned in Toronto, Kirwan has developed her own signature classes including high-intensity training (Tornado), athletic reformer training (Transformer) and a fun, challenging power yoga to the heavy beats of electronic music (Electric Yoga). You can follow her on Twitter at @lorihardcandy