You wouldn't put the wrong fuel in your car, so why put the wrong fuel in your body?

Getting the most out of your workouts depends on how you fuel up. The best foods can make or break a gym session. Often, what seems a healthy choice may not be the most effective option. Here are six foods to avoid before hitting the gym. Personal trainers from Vivotion.com have provided their advice on what a pre-workout meal or snack shouldn’t contain, if you want to achieve optimal results. Green Bananas Bananas are great - just wait for them to go yellow. The green kinds aren't great before exercising, as extra starch makes digestion challenging and could cause a bloated or gaseous feeling. Avocados They are full of the good kind of fat – monounsaturated – but any fats are hard and slow to digest meaning the stomach needs more blood, which can lead to uncomfortable cramping. Rice cakes Low in calories and anything unhealthy, but don't be fooled. Rice cakes are low in nutritional value full stop, and don’t keep you fuelled for long. Hummus A firm favourite of the health-conscious, but legumes are high in carbohydrate that's difficult to digest. This could make you gassy or bloated while working out. Chillies Though spicy foods aid your metabolism, eating a curry right before heading to the gym could cause severe heartburn. Plus, you don't want to be dashing to the bathroom instead of hitting your 1RM squat. Kale A fitness favourite, kale is a very high-fibre vegetable. While these are generally recommended, eating them before exercising could make you bloated or full of gas. Fibrous foods require extra effort to digest, which is hard when the body is focused on a work-out.

So - what should you eat before hitting the gym?

It all comes down to what kind of training you're doing. If your workout is going to be a 30-minute bodybuilding-style session, then you don't need an immense amount of carbs. This is providing you've eaten a solid meal around an hour and a half prior to training. Protein is pivotal, regardless. Some of the best protein sources include:

• Oily fish: salmon and mackerel are packed with protein and also provide brain-boosting omega 3 fatty acids
• Whey protein: there's a reason it's so popular. Whey is the form of protein powder highest in leucine, an amino acid largely responsible for muscle growth
• Turkey: also high in leucine, turkey is an extremely lean source that also contains energy-providing B vitamins and tryptophan

When the intensity of training is low, your body is in an aerobic state, turning mostly to body fat for fuel. When you begin HIIT training or performing sport, you use more anaerobic energy. Carbs are important here. Top carb sources:

• Bananas: the yellow kind, that is. These are high in rapidly-digested sugars, which you benefit from when working out
• Wholegrain or basmati rice: in addition to the gradually-digested carbs that rice powers your muscles with, the fibre will help you assimilate protein much easier
• Sweet potato: they're all the rage as fries nowadays, but there's reason for this. 100g provides less than 100 calories, but also a generous serving of performance-boosting potassium

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