Loving the Long Run
I’ve been gradually building up my weekly long slow run (LSR) and this week I’ll be out for a long 20+ miles run. Most marathon training programmes I’ve seen cap the LSR at 20 miles or about 180 minutes on your feet, rather than getting you to push on further to 22 or 24 miles. The reasons being that it’ll take your body too long to recover from that additional mileage, that subsequent training sessions would be impaired. So this season I’m planning in a few 18 and 20 mile long runs, with a half race sneaked in to refresh legs, test where I am with training and to test out those all important race pre, during and after nutrition plans.
A long slow run is demanding on your energy reserves as well as your legs, feet, heart and lungs. During a marathon, or a long slow run, your body has to draw on a number of energy sources to fuel the run. Your body’s preferred source of fuel is glycogen. However, it can only store enough glycogen to fuel about 90 minutes of running so you need to make sure your glycogen stores are full before setting out and consider taking on additional carbohydrate through the run.
In addition to glycogen your body will call upon fat, as well as protein, to supply energy to the body during a long run. So in addition to giving you confidence about running a crazy distance the LSR will be teaching your body to burn fat as fuel, so come marathon day you’ll be able to put it all into practice to conserve your precious glycogen reserves for longer.
Coaches urge us to run at slower than (marathon) race pace, and for good reason.
As you begin your run your body will start off by burning glycogen as fuel. However, as you warm up your body starts the reaction process to release fatty acids from your body’s adipose tissue fat reserves (this process is called lipolysis), which then become available as a fuel for your muscles along with glycogen.
As you reach and sustain running at a moderate intensity the lipolysis process gets going and starts to work at three times its earlier rate, increasing the supply of fatty acids to the muscles that need them. The longer you can maintain that “easy” pace the longer you’re be calling on fat reserves as fuel, and saving conserving precious glycogen.
However, since glycogen is used along with fatty acids for energy that glycogen wont last out for a full 3 hours or 20 miles, so you’ll need to have a carbohydrate fuelling plan that works for you. I use 25g sports gels, which I take every 45 minutes. These provide an immediate glucose hit into the body, but they’re not tolerated by everyone. If gels are not your thing take a look a jelly babies, an energy drink, bananas or dried fruit. It’s essential you practice your race nutrition in your training runs, as you need to make sure that your choice is easily portable, accessible whilst running and give you no gastro intestinal issues whilst running! Each brand of sports gel and drink has a different effect on runners. I once had a very bad experience taking a sports drink during a 20 mile race, that I’d previously had no issues with drinking before a race. Go figure!
The day before your long run is crucial to its success. You need to make sure that the day before you completely top up your glycogen stores. The most effective strategy is to have four to six carbohydrate snacks or meals the day before, rather than loading your body with a heavy pasta during the evening.
So think about what snacks you’ll eat the day before. Bananas are great, other options include oat cakes, malt loaf, porridge/oats, couscous, sweet potato, toast and bagels. A high carbohydrate meal, based around pasta, rice or potatoes is great for an evening meal. Without fail before a long long run or race I have macaroni cheese the night before.
Depending upon what time you’re planning on running you also need to think about breakfast, to top up glycogen stores depleted during your night fast, lunch and snacks; and when to eat before heading out.
There’s a dilemma. You need to make sure your glycogen reserves are full, but you shouldn’t be eating too soon before your run. If you’re having a meal before your run, you need to make sure that this is eaten no less than 2 hours before running, and if you’re wanting a pre run high carbohydrate snack, such as a banana or energy drink, you should make sure that is taken at least one hour before you head out.
Why is this?
When you consume carbohydrate this causes a rise in the body’s insulin levels. Unfortunately the process of lipolysis is slowed down by insulin in the blood, so fewer fatty acids are released from your adipose fat tissue, fewer fatty acids reach the muscles to be used for energy, meaning the body has to rely on glycogen for energy.
So, if you’re planning an early morning long run, you really need to be getting up good and early to eat a high carbohydrate breakfast at least one hour before heading out. Having this knowledge has completely changed my pre race nutrition strategy. I used to eat a banana and have a sports drink 30 minutes before the gun to ensure I had sufficient carbs available to fuel me. Turns out I was fuelling all wrong!
So this weekend, let’s hope the weather holds for some great sunny long runs and you have found the information shared here useful to fuel your training.
If you’d like advice and guidance with your Half or Marathon Training Nutrition email Helen@wentworthwellness.co.uk