COACHING
NUTRITION
enhanced recruitment of motor units , which may give athletes a ‘ buzz ’ and mask fatigue .
Caffeine Kick
In January 2004 , caffeine was taken off the World Anti-Doping Agency ( WADA ) list of banned substances used in competitive sports , but earlier this year it was placed back on the WADA monitoring list , and may be put back on the list in 2018 , once studies have been done this year . – BY CHRISTINE PETERS , REGISTERED DIETICIAN
Caffeine is the best known member of a family of naturally occurring stimulants found in leaves , nuts and seeds in over 60 plants , and dietary sources include tea , coffee , chocolate , soft drinks and energy drinks . Typically , these provide 20 to 200mg of caffeine per serving . The main source of caffeine in sports drinks , gels and supplements is guarana .
It ’ s well-known that caffeine makes us more alert and delays sleep , and it ’ s also popular among athletes , since it can improve performance in some sports . Caffeine has a complex range of actions on the body which have been extensively researched . It has several effects on skeletal muscle , and through some of these actions , caffeine may stimulate fat metabolism during aerobic exercise , ‘ sparing ’ glycogen stores and thus delaying fatigue .
However , other studies have found this effect to be short-lived and confined to certain individuals only . Caffeine has also been found to have other effects on the body that may influence athletic performance : It may affect the central nervous system , such as reduced perception of effort and
Caffeine Dose
Caffeine is rapidly absorbed , reaching peak concentrations in the blood within an hour after ingestion , and studies point to smaller amounts taken in throughout exercise being beneficial for performance , rather than one larger dose one hour prior to a bout of exercise . It ’ s also thought that as an athlete fatigues during exercise , they become more sensitive to small doses of caffeine . Looking at various studies , it seems that beneficial effects from caffeine occur at very modest levels of intakes ( 1 to 3mg / kg body mass or 70 to 150mg caffeine ), when taken prior to or during exercise . ( One cup of coffee can contain anywhere between 25 and 214mg caffeine .)
It is important to remember , however , that caffeine-loading is not good for all athletes . Like any drug , caffeine affects everyone differently . Some athletes will respond and receive a pronounced performance boost , whereas some athletes are non-responders , or may even experience disadvantageous side-effects that are detrimental to performance , such as tremors , increased heart rate , headaches and impaired sleep . However , contrary to popular opinion , caffeinated drinks do not dehydrate us , especially if we are used to caffeine .
In terms of long-term health , people often ask whether caffeine is safe . Right now , it appears that a moderate caffeine intake does not increase the risk of developing cardiovascular disease , osteoporosis or cancer , but as with most things , the most important thing to remember is everything in moderation ! For the average healthy adult , moderate caffeine intakes pose no health risk , especially if we eat a balanced diet and enjoy regular physical activity .
About the Author Christine is a registered dietician based in the Johannesburg area . not require extremely large weights . With the right guidance , strength training could be safe and beneficial for all runners , regardless of age .
Physical activity slowly breaks the body down , causing micro damage to the muscle cells in particular . The more demanding an activity is , the greater the rate of breakdown ( catabolism ). During the rest periods following activity , the body enters a state of rebuilding ( anabolism ). Together , these processes form what we call the metabolism . Older runners may notice that they take longer to recover from training , because as the body ages , it becomes increasingly poorer at rebuilding damaged tissues , thus the body requires more time to mend . Older runners may therefore find some benefit in trimming down their weekly mileage and spending some of the extra time recovering from exercise .
With the body requiring more time to recover from moderate / high intensity exercise such as running , and requiring more attention to strength and flexibility training , it may be worth exploring alternative forms of exercise , particularly those of low intensity . An older runner may find more benefit swapping a tempo or speed session for a yoga or Pilates class , allowing the body some respite from intense exercise while enhancing strength and mobility .
About the Author Ernest is a biomechanical , video , and running gait analyst at the High Performance Centre ( HPC ) of the University of Pretoria .
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