Does exercise eliminate heart attacks, how much should I drink when exercising, and what causes fatigue

Does exercise eliminate heart attacks, how much should I drink when exercising, and what causes fatigue

Dr. Tim Noakes is a leading scientist in the exercise physiology world and has contributed significantly to our understanding of exercise and sport and recreation. This TED Talk: TEDx Talk on Exercise by Dr. Tim Noakes is a 15-minute summary of some important research that should be watched by anyone currently exercising or contemplating exercise as part of their lifestyle rituals. Dr. Tim Noakes is UCT Professor of Sports Science and co-founder and executive director of the Sports Science Institute of SA.

For those who may not have the patience to watch 15 minutes of interesting science, I have summarized the important parts of his talk below. It is however, still important to listen to Dr. Noakes since he is a terrific speaker and the slides, images, and videos he presents are compelling.

  1. Exercise such as distance/marathon running reduces the risk of heart disease but does not make you immune from having a heart attack.
    • Identify and manage all of your cardiometabolic risk factors;
    • Begin and maintain an exercise ritual that meets your goals and is medically safe.
  2. During longer exercise rituals, particularly longer-distance events in the heat, drink when you’re thirsty not based on a schedule of drinking. This is to prevent exercise associated hyponatremia (low sodium) from over dilution of the blood which can lead to pulmonary edema, cerebral edema, and death.
    • Begin a longer exercise event by quenching your thirst and drinking up to one or two cups of water;
    • During the event drink when you become thirsty;
    • There’s no evidence sports drinks (a possible cause of exercise associated hyponatremia by promoting over-consumption of fluids) improve performance.
  3. Muscle fatigue is purely an emotion regulated by your brain and significantly affected by your mental state. Instead, fatigue is regulated by the Central Governor Model of Exercise.
    • Your brain regulates muscle performance which feeds back to your brain;
    • Your ancestral mind protects you from over-exercising because of the perception of exertion and an assumption of reserve,  and this is experienced by your conscious self as fatigue;
    • Do not confuse fatigue with muscle pain however, which is due to lactic acid build-up, the accumulations of products of metabolism  and muscle injury;
    • Motivational factors that enhance athletic performance include the presence of competitors, the knowledge of the endpoint, set deception, and a very strong sense of self belief.

Dr. Randy Knipping BSc MD CCFP FAARFM ABAARM
Lifestyle Medicine & Integrative Health

More Articles


Dr. Randy Knipping
Dr. Randy Knipping, Deerfields
randymch@sitedudes.com

Dr. Knipping has over 25 years of experience in clinical practice ranging from aerospace, emergency, forensic, occupational, preventive and integrative medicine.