Don’t be fooled by the word “bonking” – it is not what you thinking of. Bonking is also referred to as “hitting the wall” and what it is, is the sudden loss of energy you may experience in the later stage of a race if you have got your nutrition and/or hydration strategy wrong.
One of the biggest mistakes an athlete can make is to be caught up in pre-race excitement and buy all sorts of sports foods or drinks that they haven’t used before. Another common failing is to “just wing it” and rely solely on what the seconding tables have available, especially if it is things you are not used to.
What you eat/drink and when can have a huge impact on your race result and the longer the event, the more important this becomes…obviously one would be able to cope a lot better with winging a 21 km that they would on Comrades.
Eating and drinking while racing is a hugely individual thing and what works for one may not work for another. When it comes to hydration, all of our kidneys work at different rates, some may be more susceptible to functioning less effectively, and we all sweat at different rates. When it comes to eating, some people immediately suffer from GI distress (referred to in some circles as a “boskak”) from sugary things like energy gels, whereas some people are able to use them with no adverse effects at all.
Eating before an event is also something that needs to be practiced, and for some started. Rule of thumb is that if your event is less than 2 hours, you may be able to get away without eating anything. Longer than that and you will probably be better off having something to eat 2 – 3 hours before the start. Again, you need to find something that sits well and settles before the start gun – for some it is eggs and bacon, for some it is a smoothie.
The point is, get advice from someone who knows how to work out your specific needs on race day and make sure you do this with plenty of time to practice it in your training building up to the event.
Just a note with regards to pain killers on race day – beware! Non-steroidal anti-inflammatories (NSAIDs), such as Myprodol, inhibit prostaglandins, hormones that help normalize blood flow to the kidneys. Mix an NSAID with physical exertion and dehydration, and you can overwhelm your kidneys.
NSAIDs can also bump up your blood pressure. The exercise is already increasing your blood pressure, and so if you have a history of high blood pressure, this could lead to a mini stroke or a heart attack. NSAIDs also block an enzyme called cyclooxygenase (COX) that normally protects the heart, and this might explain why many NSAIDs may raise the risk of heart attack.
Some forms of COX also protect the stomach lining from digestive acids, so when an NSAID blocks this enzyme, you may experience nausea, diarrhoea, intestinal bleeding, and cramps. When used during a marathon or ultra, NSAIDs also seem to boost the risk of hyponatremia, an electrolyte imbalance that can cause the brain to swell, which can lead to death.