Written by Personal Trainer Steven Costello ACE CPT
If our goal is to lose body fat, it is best to perform Cardio exercise that is moderate intensity. Our individual health levels give us a clue as to how we should safely and non-invasively prepare for our Cardio (Aerobics). Overall it is best to have your blood glucose (sugar) levels in the ideal zone before beginning. The lower our blood glucose levels are then the healthier we should be to widthstand the strain of Cardio with energy levels from glucose diminishing. Also, the lower the blood glucose levels the more we need to stay moderate with our intensity so as to not cross the Anaerobic Threshold. If we feel glucose levels are to high (from the last meal being too close in timing to our Cardio for example) then a good plan is to first bring down the levels of glucose for fuel and still meet our demand for oxygen, which is an aerobic state, so that there is a possibility to burn fat for fuel. But if we are working too hard we would no longer supply enough oxygen to meet the demands of the muscles and then we would require more fuel than just glucose and glycogen, and without adequate glucose for fuel our bodies would start breaking down muscle tissue to use for fuel, build lactate in the blood, and we would soon tire out and would not be able to continue much longer. So, working too hard during Cardio would cross us over into the Anaerobic Threshold, when the Cardio would no longer be aerobic but become anaerobic due to the body needing glucose for fuel. Since there is an inadequate supply of glucose our body will break down muscle for fuel and thus move us backwards and the muscle loss will weaken us, slow the metabolism down and with less muscle we would have less of a capacity in our bodies to burn body fat, as fat is burned in the muscles.
When to perform your cardio is an important consideration as well. Many have had good results immediately following an anaerobics workout, and also before breakfast or before a meal when blood glucose levels are lower. However before breakfast is very risky as we have not had a meal since the night before (approx. 10-12 hours) and cardio before breakfast can be a strain on the body without nutrition for energy. Some younger perple and athletes may be able to handle that type of strenuous training, but many of us (especially older people weakened from sarcopenia) can not, so then it would be best to perform it with ideal blood glucose levels..
It is best to always experiment to see what techniques and approaches work best for you.
The subject can be explored more deeply, but to keep it relatively simple we perform cardio with the objective of conditioning our heart and lungs (rather than thinking that we are burning fat when performing it), keep synergy with the four balanced quadrants of anaerobics, cardio, eating supportively and proper rest (along with ideal blood glucose levels throughout the day with caloric balance) – and we have put in place the conditions for fat loss.
For more information on cardio exercise and weight loss, check out my 308 page book The Fitness Quadrant and my web site:
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