Hi GI Carbs

In the last post I discussed how carbohydrates affect fat storage and how to stabilise your energy levels to avoid a crash in the ring.

This time I’ll turn my attention to the stored carbohydrate (or glycogen) in your body, fuelling physical performance during longer duration training sessions between 1 and 2 hours, and multiple training sessions in one day. Unlike fat storage, your body can store only a limited amount of carbohydrate in both the muscles and the liver – only enough to fuel approximately 60-90 minutes of high intensity Muay Thai training.

Therefore, although carbohydrate intake isn’t necessary for short duration training sessions or events lasting 60-minutes or less, if you’re training for extended periods or using intermittent, high-intensity exercise like pad rounds, then you must take on some carbs during training. Running out of stored muscle glycogen results in premature fatigue and increased perceived effort, and a less than productive training session!

The glycogen stored in individual muscles can only be used to fuel that muscle, it can’t be shared with any other muscles. For example, if you’ve thrown lots of round kicks for the first 90 mins of training, your calves will be depleted of glycogen (energy), and they can’t borrow from the spare glycogen remaining in your chest. Although your liver’s glycogen store can supply on demand via the bloodstream to any muscle in the body, its main function is to ensure your brain isn’t starved of fuel. The most effective way to re-stock your calves is to consume additional carbohydrate, which is transported via your bloodstream to your empty calves.

Training between 1 and 2 hours

Evidence shows that during medium duration training of up to 2-hours, extra carbohydrate intake will delay fatigue. It’s recommended that 60g of carbohydrate per hour in the form of glucose or maltodextrin is ingested. This can be consumed in any form – solid, liquid or gels, entirely dependant on personal preference. I personally prefer drinks as the liquid carbohydrate has the added advantage of preventing dehydration – and I sweat like a pig. Drinks alone can make some people feel nauseous. If this is you, try some high GI carbohydrate foods such as cereal bars or white bread sandwiches.

My favourite training drink is pure orange juice diluted 50:50 with water. This tops up my glycogen stores and is an isotonic rehydration drink. Particularly important when training in hot, humid climates like Thailand.

Training over 2 hours

If you’re training for longer than 2-hours it’s recommended you consume 90g of high glycemic index carbohydrate per hour. To achieve this I top up my orange juice drink with high glycemic index foods like cereal bars.

Multiple training sessions in one day

In Thailand, it’s common to train in the morning and the afternoon. To get the best out of these sessions you should optimise your short-term recovery and begin taking on carbs as soon as possible after training. Research shows that if carbohydrate alone is being used, then supplementation should be very frequent, such as every 30 minutes 1.2 to 1.5g of carbohydrate per kg of body weight should be consumed for up to 4-hours.

Studies have also shown that combining carbohydrate with protein increases the rate of glycogen storage. If this method is used, the recommendation is that 0.8g of carbohydrate per kg of body weight plus 0.2g of protein per kg of body weight (4:1 carb/protein) be consumed immediately and 2-hours after exercise during a 4-hour recovery period. This carb/protein method of replacing muscle glycogen also has the added advantage of promoting repair of damaged muscle tissue.

If you want to get your calculator out, then go for it (I must admit, I do). But the take-home point is get some carbs down you ASAP after training – it’s more important than protein (although some protein won’t do any harm). All of these refuelling strategies have a significant impact on subsequent physical performance, and play an important part in a Thai boxer (of any level) achieving their personal best.

Part 3 of this post looks at the role of carbs when cutting weight for a fight. As always, post a comment below if you want more info or just to get involved.

Further Resources

Don Heatrick

Founder of Heatrick Strength and Conditioning

Don Heatrick is a family man from the UK, former mechanical design engineer, European Muay Thai silver medallist, former pro Thai boxer (ranked 4th in UK while aged 40-years), a Muay Thai coach, podcast host, and the go-to expert on Muay Thai performance training with over 25 years of coaching experience.

Don helps ambitious fighters and coaches take their game to the next level by bridging the gap between Strength & Conditioning, Performance Science, and Muay Thai.

Follow Don Heatrick on Instagram: https://www.instagram.com/donheatrick/

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