How to fuel correctly for your workouts to optimise your health and fitness goals

Yasmine Say
8 min readOct 16, 2022

Nutrition and physical activity, eating and exercise, moving and munching. However you say it, the combination of what you fuel yourself with and how you then utilise those calories is always a bit confusing, particularly if you understand the immense value nutrition has on your health. So read on, because that head scratching ends now, and after reading this you will be 100% certain as to what you should be turning to.


This would depend on the time of day and what you are doing.

If you are a morning exerciser and choose a gentler form of activity such as a short walk to work or a restorative yoga session quite soon after waking it might very well be the case that eating before doing these doesn’t sit particularly well with you, in which case I would say water and naturally decaffeinated herbal teas are perfectly sufficient. If you are female and happy to do so, I would think about adding a pure collagen powder into the above drinks as this gives a small amount of bioavailable amino acids to the body just so it has a little something in its back pocket to work off. Men can do this too of course but it’s less of a necessity. This is due to the more complex nature of the female body with their monthly tide of hormonal changes. Because of these they will naturally need more support than men when it comes to not perturbing their metabolism in a negative way which can happen when exercising fasted.

If you are exercising more intensely in the morning, something like a HIIT class, CrossFit, a longer walk or a swim, then I would advise either having a more substantial drink or a small snack before going — something easily digestible like a banana, some rice cakes with peanut butter, a low sugar protein bar or even a homemade smoothie. Again, the activity will matter, and you want the perfect combination that gives you something to fuel yourself but doesn’t make you feel sick whilst doing your training!

If you want to have caffeine pre-exercise, I would always encourage you to listen to what your body is telling you. Caffeine stimulates stress hormone response, exercise (that raises your heart rate) does this too, and naturally we produce cortisol in the morning (which is how we wake up!). The thing about more stress hormones circulating is that this also increases circulating insulin, and insulin is a storage hormone that prevents fat metabolism. A really big spike in stress hormones (adrenaline and cortisol) in the morning will often result in a crash later in the day and take your blood sugar down with it which can leave you feeling wiped out in the afternoon, craving sweets and potentially eating in excess of your needs which is not what we want. Conversely some people can use caffeine as a brilliant performance enhancer and not find this is an issue at all. It’s important to experiment with caffeine and what works for you, and if you do any type of intermittent fasting it’s worth knowing that that caffeine does not actually break your fast because it doesn’t impact glucose metabolism (unless you have milk added or anything that your body has to additionally digest/break down).

Back to food now though, and the key thing we’re really looking at is the gap in time between eating and exercising, as this impacts what you want to prioritise in terms of food combinations and proportions. A short gap means you want some relatively simple carbs and a bit of balancing protein and fat, but not too much as you want to get to that relatively quickly liberated energy to burn to fuel your workout. However, if we then swing to having a meal an hour or two before heading to exercise, we want things that are slower burning and sustained so they’re still ‘active’ in our systems when we go to train.

As an example, if you were going to have breakfast at a normal time at the weekend then head to a gym class or head out for a run mid-morning you would want more complex carbs such as a nutrient dense toast and protein rich topping with some nice fibrous non-starchy veg and a little bit of fat, something like scrambled eggs or tofu and a couple of handfuls of rocket/spinach or some mushrooms/tomatoes on rye with avocado. Otherwise, you may choose some wholegrain oats (ideally choose organic where you can) with nut milk mixed with seeds, nuts and some chopped fruit. If going for an oaty option, then just make sure you aren’t getting your carb-protein balance wrong — we want equal amounts of these and often recipes will swing much more to the carbs especially when toppings are added in. This is when you might think about including an innocuous veg into your oats e.g., courgette, cauliflower, or carrot, to provide bulking fibre for satiety but keep the carb content a touch lower.


As much as possible prioritise protein for the first meal of the day — around 30–55g (the upper figure if you are vegan/vegetarian). After a night’s sleep our liver glycogen is depleted to a certain extent (varies from person to person), so we are going into that first meal in a catabolic state (the process for when food molecules are broken down in the body for use as energy). Protein will prime the body for muscle protein synthesis, regardless of age, and when paired with exercise this primes the body for optimal protein ingestion.

Don’t forget however, that the body’s main source of energy comes from carbohydrates (there are some nuances here, too), but think about the quality of carbohydrates in your food and what combination of carbs/protein/fats fuels you best for your workouts, particularly when working out in the morning.


Another hugely contentious topic and this again depends on the intensity of exercise, length of time you’ve exerted for and your needs generally. It has previously been touted that you must eat within 30 minutes of exercising to ensure your body has the appropriate nutrients to repair and regenerate muscle tissue. This however has been generally disproven as your body creates an amino acid pool which serves as a mixing pot of building blocks that your system will dip into as it requires. If you are eating a well-balanced, protein rich diet there isn’t a screaming need from this angle to be having something immediately as you finish your session.

However, I will now revert back to someone’s individual needs and how this rule might differ. As I mentioned above exercise increases stress hormone levels which, in addition to increasing the presence of the storage hormone insulin, also down regulates digestive function. This can mean that trying to eat and then absorb a protein rich meal after exercising can prove quite difficult as this requires a lot of stomach acid firepower. If it’s a particularly intense form of exercise, such as spinning, this might make someone feel quite distended should they try to sit down to a wonderfully balanced and nourishing meal within an appropriate eating window to support their body’s rejuvenation process. This would be another instance where they might then misconstruct their post workout meal, or leave it too long to eat, and then find there is a resultant blood sugar and energy crash a few hours later. This is where supplementing with a protein shake, or other protein supplement may suffice. I will just confirm here that if someone were doing a more calming form of activity that doesn’t push them into their cardio red zone (some forms of yoga, restorative walks/swims, or a mobility session for example), then these impacts on digestion won’t be seen and you wouldn’t need a supplemental product.


The protein powder market is huge and there are now so many options to choose from, depending on your budget and taste. If you can tolerate dairy then choose an organic whey protein (the highest bio-available protein on the market) with no additives, if you don’t include dairy into your diet then choose a plant-based product with a mixed base (I use a great one made from pea protein), avoiding purely grain based options like rice protein. You are always aiming for the key level of 25–30g protein per serving, with ideally no binding gums, sweeteners or flavours. You also want to make sure the protein powder contains these essential amino acids — leucine, isoleucine and valine. If you will be eating a meal within an hour or so, then you can simply blend protein and a handful of greens and a few berries and either water or a milk of your choosing. If you want it to be a little more robust because you’re rushing off somewhere and will eat your next meal 3–4 hours later, then add one large handful of steamed and frozen courgette or peas, 1/2 banana or 2 tablespoons oats, and either 1/4–1/2 an avocado or a spoon of nut butter. Gain sweetness from additions like cinnamon, cacao or vanilla powders rather than sugars or sweet dried fruits if you can.

In terms of constructing a post workout meal, if it’s a relatively low intensity workout stick to regular plate proportions of 1 cupped handful of complex carbs (wholegrains, root veg, nutrient dense bread) and a palm sized portion of protein and 2 handfuls of non-starchy veg and a tablespoon of a fat rich food (avocado, cold pressed oils, pesto, nuts, seeds, olives). If you have done a higher intensity workout, then you will have burned through more of your glucose stores and will likely need to increase your carbohydrate portion by half again whilst keeping the remaining elements the same.


Unpopular opinion I’m sure, but one of my biggest bug bears is poor quality sports supplements/snacks such as energy/BCAA ‘fuel’ drinks, sweetened protein powders and recovery shakes/bars. The main reason being that these are jam packed with sweeteners. Sweeteners of any kind (including ‘natural’ options like stevia and erythritol) promise a lot and give absolutely nothing to your body. A sweet flavour suggests quickly liberated energy is coming but a sweetener as opposed to a sugar is calorie free. So your body thinks it’s getting something to fuel itself and then nothing happens. This plays negatively into metabolic flexibility and over time creates insensitivity to insulin which then causes us to hold/store fat, crave sweets and suffer energy fluctuations.

Sweeteners are also the enemy of our gut bacteria and there is a bounty of clinical evidence to show that keeping these little bugs happy and content is the foundation of long-term optimal health.

When it comes to the ready-to-eat snacks, these are often overly high in carbs and fat, as well as protein which makes them unsuitable for daily consumption even if they are marketed as such. There are some decent protein bars on the market these days that don’t have all the added ingredients that you can’t pronounce, but I would always try and choose a natural protein source such as yoghurt, cottage cheese, boiled eggs or edamame and have these with a bit of fruit instead of an expensive pre-made bar!

If you have any questions on the above, or specific Nutrition questions when it comes to your own training, please feel free to get in touch via email at



Yasmine Say

Founder of Say Fitness Personal Training. #PersonalTrainer, STOTT Pilates Instructor and Mobility Coach. @sayfitnesspt