WITS Exercise Physiology

New WITS Exercise Physiology Lab study in Cyclists

by Aletta Esterhuyse

The Wits Exercise Lab has a new and very exciting study on comparing energy drinks ingested during cycling to investigate differences in energy metabolism and of cause cycling performance. This study will help you to understand what is truly the best mix for your racing fuel.

We invite male cyclists or triathletes who match all of the following characteristics to participate:

1. Competitive male cyclists who are highly trained and include at least 12 hours cycling training per week.
2. Cyclists who are generally healthy, not on medication and are non smokers
3. Cyclists aged 18 to 45 years old
4. Cyclists who are able to visit our laboratory for 5 separate 3 hour visits on a weekday arriving at 10 am (once a week).

The study’s focus is on comparing energy drinks ingested during cycling to investigate differences in energy metabolism and of cause cycling performance. In fact, in our quick releasing energy drink (or high glycaemic index mix) we hope to use very recent updated scientific recommendations that has not as yet been applied to off-the-shelve products. This study will help you to understand what is truly the best mix for your racing fuel.

We intend comparing the following 5 beverages:

1. Placebo flavoured water
2. High glycaemic index carbohydrate only (maltodextrin+fructose), i.e. your typical energy drink but with slightly more fructose
3. Low glycaemic index carbohydrate (isomaltulose), i.e. a sugar used in some drinks such as 32GI and even USN Epic Pro
4. High GI carbohydrate with added milk protein, casein hydrolysate, i.e. energy drink #2 with added protein (Peptopro)
5. High GI carbohydrate with added milk protein, whey hydrolysate, i.e. energy drink #2 with different protein source, used in USN Epic Pro

We are looking for ten highly competitive male cyclists to take part. Each cyclist will first will undergo standard performance testing, to determine VO₂max, lactate thresholds and peak power output.  Each cyclist will then complete 5 separate experimental trial including a different energy drink during each trail. Each experimental trail will be separated by at least 1 week. During each trial you will cycle for 2 h at a fixed steady-state on our cycle ergometer for assessment of metabolism. This is immediately followed by a 16 km time trial on your own bicycle fitted to our Tacx ergometers that simulates a time trial route with real time video footage of the coarse. The programme we have chosen depicts you as an animated cyclist and looks similar to a play-station game only you have to pedal to get your character to move.

Please let us know if you are keen to be involved. We will start with performance testing mid-April and experimental trials soon after that.

You can either contact them directly or through Bio4Me and you will be provided with more details

Aletta: Aletta.esterhuyse@wits.ac.za

Tanja: oosthuyse@polka.co.za

Andries: send me an email