Carbohydrate/Fat Use During Aerobic Exercise

[notfreemoney]

Exercising at high intensities uses carbohydrate as the main fuel for energy. Exercising at lower-moderate intensities uses fat as the main energy source. However, exercising at a higher intensity increases metabolism for a longer period of time, burning off more calories. Higher intensities also lead to better physiological changes (overall more healthy body)

Heres what I dont understand. If someone is attempting to lose weight- they often follow the advice to exercise at low to moderate intensity ( its usually on cardio machines as a graph with heart rate on the y-axis and then a 'fat' burning zone somewhere on it). Does exercising at a low to moderate intensity really burn more fat in the long run? Im thinking that with the added benefits that exercising at a higher % heart rate outweigh the 'fat burning' intensity...

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