Remember, no matter how much you do at the gym it won't mean anything if your diet's in poor shape.
I do both weights and cardio, so here's what I'd suggest:
Weights:
- Timing is important and your body takes up protein and carbohydrates especially well up to 1 hour after your workout, so make sure you eat post workout.
- I go to the gym in the morning and manage to have protein. It's a good idea to have protein both pre and post workout. For my breakfast I have 40g oats, 2 egg whites, some milk and some water, mix it up and microave it on half power for 3 mins, then add cinnamon / ginger / nutmeg, microwave for another 1, stir and microwave for another 1.
- Remember that your body will build muscle for up to 4 days after your workout so keep protein in your meals, but don't go overboard and have 30 chicken breasts a week.
- Have different types of meat; not just chicken, tuna is higher in protein than chicken and salmon is high in protein and omega 3 oils. you can also get protein from nuts (which also contain good unsaturated fats) as well as yogurt (Greek is high in protein).
- To make your life easier, cheaper (and this is what I'm doing) I've bought protein powder. It's a cheap, convient way of getting your protein both pre and post workout. I got this
http://www.discount-supplements.co.uk/sports-supplements-whey-protein-optimum-health-ultimate-whey-protein-2-25kg#.UjSrJT8lOUk which is very cheap and they do a diet variety, which will help if you're aiming to lose weight. Also, it's cheap; 2 bags for £45, 4 for £80 and there's always a 12% off discount code knocking about.
-If you eat a meal before working out leave enough time for it to digest 2~hours
Cardio:
- Make sure you eat before working out, protein and carbs are good (scrambled eggs on toast) or I used to have 2 scrambled eggs.
- Although not a necessity eating post workout can help, but ensure it's a low GI carb (i.e. a fruit / veg) and don't consume starchy carbs (pasta, rice, bread) immediately after workout.
- Drink lots of water throughout.
- The breakfast I suggested above works well for cardio also however, you can substitute the eggs for one whole egg and you can add fruit to it.
General:
- There is no such thing as an unhealthy food (apart from hydrogenated fats), only unhealthy proportions. So although brown rice may be good for you, easting it in 200g portions a time carries a lot of calories. sumo wrestlers eat vast amounts of rice to fatten up.
- Make your plate colourful - you should have a mixture of colours on your plate e.g. sweet potato (orange), broccoli (green), salmon (pink), green beans (green), sweetcorn (yellow)
- Don't overdo it on the carbs, they carry a lot of calories. Pasta is about 400kcals per 100g. A little will keep you going for ages and you can always bulk up the starchy carbs e.g. brown rice becomes vegetable rice by adding onion, mushrooms, peas, sweetcorn, green beans, sweet potato etc.
- Substitute foods you eat now for healthier versions: White rice -> Brown Rice. White break -> Brown bread (although cutting out bread altogether would be ideal). White potato -> Sweet potato . White pasta -> Brown pasta
- Whole grain is better than multigrain.
- Every so often it's alright to indulge in luxuries; that last bascuit in the packet, a strip of chocolate. For example, I, whenever I eat out, have whatever I want.
- Getting your eating right is harder than the actual excersises!
- Remember, muscle grows when you're resting.