Do you often struggle to get out of bed in the morning? Feel you need to have a quick doze at your desk in the afternoon? Or find that you're lacking in energy when you start your run or workout? Whilst there can be many contributing factors to this feeling of fatigue, one of the most significant is likely to be your diet.

January blues: Whether you're a seasoned runner or a beginner, most people find the cold, dark mornings and evenings of January cause a sense of lethargy. To ensure that you maintain your training, you need to look carefully at what you're eating - or not eating - and consider how it affects your energy levels. Snacking on small meals every few hours, rather than just eating two or three main meals a day, is the best way to fuel both your mental and physical energy.

Off to a good start: It sounds like an old wives' tale, but breakfast really is the most important meal of the day! Going without means you're neither at your best whilst at work, nor during your morning exercise. Your brain is governed by fuel and nutrient supplies so, after a long night without food, your blood sugar levels need topping up. The choice of convenient breakfast cereals these days is vast, with porridge heading the list of great ways to start your day. If your excuse is lack of time, fresh fruit and yoghurt, a fruit smoothie or a wholegrain muffin are easy to eat on the go.

Hydrate your brain: We all know that we should drink enough water, but often the temptation of a cup of tea or coffee proves too much. If you do give in to caffeine, try and make up for the consumption my having an additional two glasses of water. Drinking too little water, combined with fluid loss caused by dry indoor air, can leave you feeling tired, dehydrated and headachy. Drink little and often from a bottle of mineral water throughout the day. Read our full advice on hydration here

Caffeine addiction: Drinking a cup of tea or coffee seems to make you feel more alert for a period of time. But it's surprisingly easy to become dependant on caffeine and get into a pattern that actually causes fatigue. It can then be difficult to cut down on caffeine as, initially, this makes you feel tired and irritable. Try cutting down gradually, phasing out a little more every time your body adjusts to the new amount. Herbal teas are full of goodness and offer a hot alternative.

Essential minerals: Raisins, apples and nuts are good sources of 'boron', a mineral thought to help with brain functions, such as memory, attention and manual dexterity. By adding a handful of raisins and nuts to your cereal or lunchbox, you could reduce the feeling of afternoon drowsiness. 'Selenium' is another mineral thought to clear your head and lift your mood. Tuna and brazil nuts are excellent sources of selenium, which is also found in chicken, turkey, lean beef and wholegrain cereals.

Light lunch: After a busy morning at work, the temptation is often for a hearty lunch to refuel for the afternoon. Unfortunately, whilst you may have enjoyed your lunch, it's almost certainly going to leave you feeling very sleepy in the afternoon. Your body will utilise any available energy to digest your large lunch, which leaves your brain significantly lacking in resources! Stick to a light lunch, which will be plenty if you follow our breakfast tip.

Filling fibre: If you're used to eating a lot for lunch and find that a small lunch doesn't keep you going for long, add some fibre to your lunch or as an afternoon snack. This is the ideal time to build up to the recommended 'five-a-day' portions of fruit and veg. by snacking on fruit such as apples and oranges, which are good sources of 'pectin' - a type of fibre known to make you feel full for longer.

Sensible snacks: An afternoon snack can give you a boost if you're feeling generally tired. Avoid crisps and chocolate, though, and opt for something nutritious and rich in carbohydrates. We recommend bananas - full of carbohydrates and a good source of vitamin B6; raw carrots - low calorie, filling and containing carotene and vitamin A; low calorie cereal bars - contain vitamins and iron as well as satisfying sweet cravings; dried apricots - low fat, high carb with vitamin A, fibre and potassium; fruit yoghurt - highly digestible source of calcium, protein and potassium; houmous on pitta bread - more filling with the benefits of protein, fibre, vitamin B6 and folic acid (although can be high in fat); or rice cakes with peanut butter - energising carbs with the addition of protein and vitamin E.

Don't be tempted by radical diets: A lot of people set about trying to lose weight in the New Year and it seems as if a different new-fangled diet comes along every week to offer a quick fix method of weight loss! Be warned: A radical reduction in calories is certain to leave you feeling drained of all energy, affecting both your mental and physical performance. It can be hard to ignore the hype of diet gurus, but the most effective way to lose weight will always be to increase your level of exercise and eat a healthy, balanced diet.

Listen to your body: It's normal to feel tired after a hard run or workout, but if your body is suddenly unusually tired, recognise the signs and pay more attention to your diet before your next session. Eat slow releasing carbohydrates before training to ensure that your muscles have enough fuel to keep you going. If you still feel fatigued, your body may just be telling you that it's time for a rest!