What to eat, how much to eat and when to eat is very much an individual matter to fine tune, but knowing the basics of fuelling can help guide what you choose to do. Whether you are training for your first summer trail run or are an avid exerciser, having the correct nutrition is key to making exercise enjoyable and sustainable. The type of exercise (anaerobic vs aerobic) and the duration (short vs endurance) will be fundamental considerations in nutrition planning, but the bottom line is our bodies need fuel to move.
Carbohydrates have once had a bad rap, but anyone who has done endurance sports will know why they are your best friend. However, they are not just for the endurance athlete. Carbohydrates are the easiest of the nutrients to metabolise (break down) to produce glucose - our bodies’ principal source of energy. When we eat foods rich in carbohydrates, our body can convert it to glucose for the immediate provision of energy or if not yet required, our body will store the glucose in our muscles as glycogen. When we require energy, our body will convert the stored glycogen back to glucose. Because of being a readily available source of energy, carbohydrates are an important nutrient pre, during and post exercise.
A carbohydrate rich snack 30 - 45 minutes before your exercise can help top up your glycogen stores, and provide the body with readily available glucose. For those exercising less than 60 minutes, this should provide sufficient energy for your workout. If you are exercising for longer than 60 to 90 minutes, you will need additional energy from carbohydrates during your session. As a starting point, aim to start fueling within the second half hour of training, and then look to consume about 60 grams of carbohydrates each hour of exercise. Examples of how you might get 60 grams of carbohydrates in are from gels, sport drinks or bars, lollies or whole foods such as bagels, jam sandwiches, fruit puree etc. Finding what works for you (and your stomach) can require some trial and error. If you are unsure of how well you will tolerate different carbohydrate rich foods during exercise, start with a lesser amount per hour and work up until you find your personal balance.
The priority with post exercise nutrition is about replenishing your glycogen stores and setting your body up to recover. Protein helps in building and repairing our muscles. Most recreational athletes will find that if they are consuming sufficient calories in their diet, their protein needs will be met without needing to add more. The timing of protein rich foods is where benefits can be seen. Ingesting a good quality protein and carbohydrate mix snack within 30 minutes of finishing exercise has been shown to have benefits for muscle recovery and therefore supporting one's ability to perform at their peak in future exercises. A glass of chocolate milk, cheese and crackers, your favourite nut butter (Fix & Fogg hehe) with fruit are examples of what a protein/carbohydrate mix snack post exercise can look like.
Fats can be often overlooked as playing a healthy part in fuel for the recreational athlete. Fats have a role in providing needed energy in the form of calories. Fats also help our bodies to absorb some important vitamins, namely vitamins A,D,E and K. Foods such as avocado, nuts and seeds, fish, or using olive or vegetable oil as a salad dressing base are great ways to incorporate healthy fats into our daily diet.
Fats rarely make up 100% of the food composition we are eating at a meal or snack time. Fat slows the digestion of food, and will slow the release of glucose from carbohydrate foods ingested at the same time. This has the benefit of leaving us feeling full (satiated) for longer. This however means foods high in fat are not a great fuel source during exercise, when we are needing to quickly access energy in the form of glucose.
Last but certainly not least – fluids. Keeping hydrated throughout the day and during exercise is important for both training and recovery. I am personally guilty of neglecting fluids, and paying for it in feeling sluggish, and slower to recover post running. For light, sh
ort duration activities under 60 minutes, water is generally sufficient. For longer, moderate to strenuous sessions, or sessions in the hotter temperatures, where you may be losing large amounts of fluid through sweat, fluids containing electrolytes are recommended. As a rule of thumb, having a light straw colour pee is a good indication of hitting the mark on hydration. Any darker and you are moving towards a dehydrated state.
Optimally fuelling for your exercise does not need to be complicated, but it is an individual journey that will often involve trial and error. I hope this article has provided you with some tools to understand what nutrients and how to best time what you eat, and can support your exercise goals.
Edith is a New Zealand Registered Dietitian, originally trained in Canada. She has been physically active most of her life, having enjoyed track and field days in her youth, and maintaining her love for running throughout her adult life. For Edith, now nothing quite beats a sunny day running on the trails before diving into Wellington’s icy cold waters.