The energy equation

When it comes to weight loss, diet and exercise go hand in hand. While it is perfectly possible to lose weight through either dieting or exercising alone, the process will be much lengthier (and can be de-motivating if you are not seeing a good rate of progress) than if you tackle both ends of the energy equation, in other words, take in less calories through eating the right foods and use up more calories through regular exercise.

Much less well understood is doing the right type of exercise to achieve the results you want. I have often heard people complain that despite doing two or three hard workouts at the gym each week, they cannot seem to shift the weight.

My answer is that they are probably exercising too hard. Although hard training sessions will improve cardiovascular fitness, it can have less impact on weight loss, especially if you over compensate with food later. During high intensity workouts your muscles use up stored carbohydrate for energy. After you have finished stores are depleted and blood sugar levels can dip, this makes you feel hungry (in fact sometimes ravenous), so naturally you eat.

However, you are likely to eat just as many calories that you have used up, which means you have not created the energy deficit needed to lose weight. Of course there are benefits to heart health and metabolism from this kind of exercise but it is unlikely to have the kind of impact you want to make on losing weight. Furthermore, hard sessions of high intensity exercise are not recommended everyday, your body needs to recover and rest in between, so again this reduces the chances to create an energy deficit each day.

It is recommended that adults aim for at least 30 minutes of exercise 5 times a week. These sessions should ideally be a combination of cardiovascular (jogging, swimming, cycling) and weight-bearing exercise (weight training, yoga, pilates) for optimum health. This is good advice, so below we show you how to choose the correct type of exercise and the best foods to compliment to achieve the results you want, whether weight loss, improved fitness or muscle strength.

To lose weight

The best exercise to help you lose weight are low intensity fat burning activities. Walking is perfect. Low intensity exercise keeps your heart rate lower and this allows your body to use up fat stores rather than carbohydrate stores. This means that when you have finished you won't feel tired or hungry. Walking uses up about 4-6 calories a minute depending on your pace. So aim for a 45 minute walk to use up a good 225 calories. If you do this everyday, that's 1575 calories a week which equates to nearly half a pound. Combined with a healthy eating, you should have no trouble losing 1-2 pounds a week.

You don't need to eat anything before or after your walk, but it is a good idea to drink water, before, after and during, especially if it's a hot day. This will help you feel more energised.

If you feel you need a reason to walk, try incorporating it as part of your journey to work, or part of another daily routine, or consider getting a dog, they force you to go out in all weathers!

To improve stamina and endurance

The key to endurance is carbohydrate. If you do a lot of high intensity training such as long distance running or cycling or train regularly for football or rugby matches, your diet should always be high in carbohydrate as this is the fuel your muscles will use whilst you exercise. The night before a heavy training session, race or match, aim for a carbohydrate rich meal to boost carbohydrate stores in the muscles and the liver as much as possible. A mix of fast- and slow-acting carbohydrates will ensure levels are topped up.

Hard exercise can weaken the immune system and cause damage to tissues by the increased production of free radicals, so plenty of fruit and vegetables are needed to provide antioxidants, which helps prevent damage and boosts the immune system. Potassium levels should be topped up before exercise to prevent excessive losses caused by sweating.

Try this eating plan if you have an important event coming up:

The night before

• Homemade vegetable pizza: take one base and spread with a small jar of pizza sauce topping, add a small can of tuna, add lots of chopped up vegetables - half a pepper chopped into strips, 3 sliced mushrooms, 3 slices of onions pulled apart into rings, a few olives and capers and top with 3 tbsp of half fat grated mozzarella
• Small tub of potato and spring onion salad in a low fat dressing, served on a bed of watercress
• Bowl of mango sorbet with chopped mango pieces

Breakfast (to be eaten 3-4 hours before event)

• 200g of porridge or instant oats, add 4 chopped semi-dried apricots
• Glass of apple juice

The porridge oats, dried apricots and apple juice all have low GIs, which means their carbohydrate energy will be released steadily by the time the event starts providing a constant supply of glucose into the bloodstream to be used by the working muscles. This spares the glycogen stored in the muscles and liver and stops you from hitting the wall (caused by exhausted glycogen stores).

Pre-exercise snack (30 minutes before event)

• 200ml isotonic sports drink
• 1 ripe banana

An isotonic sports drink will deliver the last blast of glucose to the bloodstream and ensures you are well hydrated as it's special composition means it is the fasted way for the body to absorb water.

A ripe banana has a higher GI than greener, under-ripe bananas, so the carbohydrate energy will quickly be absorbed into the bloodstream.

Post exercise snack (to be eaten immediately after finishing)

• Pitta pocket filled with 2 tbsp. reduced fat hummus, half a grated carrot, half a pepper chopped into strips and a handful of shredded lettuce
• Carton of orange juice
• Box of raisins

Eating some fast-acting carbohydrate as soon as you finish (even if you don't feel like it) is the quickest way to recover. The pitta, orange juice and raisins all have high GIs, which means their carbohydrate energy will be quickly available to restore glycogen levels and help muscles recover.

The hummus provides some easily digested protein to help muscles repair themselves.

The carrot and pepper are good sources of beta-carotene, an antioxidant needed to boost the immune system and to prevent free radical damage caused by exercise.

The orange juice is a good source of vitamin C, and potassium is supplied by the juice and the raisins which can help replace potassium lost through sweating.

To improve muscle strength

There are four major nutritional strategies for achieving optimum results from strength training:
● Water - to replace fluid lost as sweat and to aid
the process of ‘glycogen fixation' (carbohydrate storage ready for the next training session);
●Electrolytes - to replenish minerals lost in sweat
(e.g. sodium, potassium, chloride);
●Carbohydrate - to replenish muscle glycogen, the
body's premium source of fuel for strenuous exercise and also to top up liver glycogen stores, which serve as a reserve to maintain correct blood sugar levels;
●Protein - to repair and regenerate muscle fibres damaged during exercise, to promote muscle growth and adaptation, and to replenish the amino acid pool within the body.

The highest muscle rate of carbohydrate replacement is achieved when large amounts of rapidly absorbed (high GI) carbohydrate (1-1.85g per kg of body weight per hour) are consumed immediately after exercise and at 15- to 60-minute intervals thereafter, for up to five hours. Delaying carbohydrate ingestion by several hours may slow down replacement of the carbohydrate stores.

Also the presence of amino acids (components of protein) in the bloodstream and their availability to muscle cells is vital for protein synthesis after exercise. Different proteins are digested at different rates, the most rapidly digested protein is whey, found predominantly in milk and dairy products. Once digested, whey protein delivers high levels of branched chain amino acids that seem to stimulate growth and repair of the muscles.

Ideally, a post-muscle workout snack will provide 1g of carbohydrate per kilogram body weight and 0.5g of protein. This should be consumed along with a bottle of water within 30 minutes of finishing training, followed by a high carbohydrate meal within two hours.

Click here for some quick and easy ideas for post-training snacks