So, you’ve started running and you’re not sure if you should be making changes to what's on your plate? Maybe you took up running because you wanted to lose weight, so in turn you have paired your increase in exercise with a decrease in your food intake? Perhaps you started running for enjoyment or you’ve signed up for a race and you’ve found out that running makes you REALLY hungry and now you're snacking all the time? Let us help…
There is nothing wrong with having weight loss as a goal when it comes to running, but I would suggest that during the first few weeks of training you do not restrict your dietary intake, and here’s why. If you’ve increased your energy expenditure, but reduced energy intake this could result in a caloric deficit that is too great. This could lead to fatigue, brain fog, plateau in performance and increased risk of injury. If you keep your food intake the same and introduce some training steadily, you are most probably already creating a calorie deficit. Hopefully this is a deficit that is maintainable, one that will allow for slow and safe weight loss. If you have been adhering to your Runna plan for more than three weeks and your weight is still the same or increasing then you can look to make changes to your diet, but I would recommend avoiding trying to do everything all in one go.
Adjusting your diet over time
Most of you have probably started running with the main goal of reaching a certain speed or distance. The majority of new runners will choose the Runna ‘New to running plan’ which takes 8 weeks to build up to 5km. The runs within this plan start off pretty tame, and so during this time you probably don’t think you need to make huge adjustments to your diet. However, as things progress or better still, you move onto a longer distance plan, you are definitely going to need to make some changes to your diet as your energy requirements will increase. You might have already noticed this as your appetite has probably ramped up and you are likely struggling to curb it. There is nothing wrong with snacking, in fact I actively promote it, but don’t be afraid of increasing your meal sizes if necessary. Otherwise you’ll find it's very easy to end up consuming most of your energy in snacks and not as well rounded meals.
You need to ensure that you are eating a sufficient amount of food so you have the energy to complete your training to your full potential, as well as enough to recover and make physiological adaptations from your sessions. There is no point smashing your runs if your body doesn't have enough energy to produce more red blood cells, repair your muscle fibres and restore muscle glycogen levels. Make sure you are eating enough to maintain the energy levels needed and stay injury free!
In regards to your weight, you do not need to weigh yourself, this can simply be done on how your clothes feel. A small fluctuation in weight is normal but if your weight is yoyo-ing between clothing sizes, always increasing or always decreasing then you will know you are not consuming the right amount of energy.
Hold up, it's not just about energy in and energy out, the quality and diversity of your food is incredibly important.
Protein is going to become a very important macronutrient because as a new runner you are going to be using muscles that may be underdeveloped. When you run you will cause microscopic damage to these muscles. In return your body will repair this damage and produce more muscle fibres so it can better cope with its new demands. If you are not consuming enough protein this growth and repair cannot occur. This is why you may feel a plateau or drop in performance and may even find your risk of injury increases. Your daily needs are around 1-2 grams of protein per kilogram of body weight (e.g. 70-140g for a 70kg human).
The next macronutrient to turn your interest to is carbohydrate. For those of you new to running, you will need around 3-8 grams of carbohydrate per kilogram of body weight per day (e.g. 210-560g for a 70kg human). This can go all the way up to around 12g/kg BW when you get up into the marathon and ultra world. In next month’s blog I will be covering carbohydrate availability and its importance for performance, recovery, gut health and hormonal health, so don’t fear, there is more on this coming your way soon!
Fat is the often forgotten macronutrient. It is incredibly important for nutrient transport and hormone regulation. I’d suggest you aim to have consume 1g/kg BW per day of fat in your diet (e.g. 70g for a 70kg human). The majority of this should be sourced from ‘healthy’ fats such as nuts, seeds, avocado, olive oil, oily fish etc.
Keep it simple
We could do a deep dive into micronutrients but that’s a whole article on its own. The simplest place to start here is to add as much variety to your diet as possible to increase your chance of consuming enough of everything. It may sound cliche but ‘eat the rainbow’. Try not to stick to the same 5-a-day every day but aim for 30 different plant foods a week (e.g. vegetables, fruit, nuts, seeds, beans grains and legumes).
When you are new to running, there’s no need to over complicate things by wildly changing your diet on your run days in comparison to your rest days. The body does not completely reset every 24 hours. It is an ever moving time continuum, and you may actually feel more hungry on rest days as your body has the time for recovery which takes a huge amount of energy.
A final side note… none of the above means you need to track your food and obsessively read food labels. It is here simply to offer some guidance so you can make better, more educated decisions around fuelling your running and your life.
Emily (one half of @twicethehealth)
ANutr, MSc, BSc