Nearly passed out again at the fitness club. Likely the result of two factors. First, we were working out the legs quite intensively with a step-board. My lower extremities probably hogged all available blood, leaving little for the brain. Starved of oxygen, brane go by by.
Second, insufficient calorific intake. My last meal was six hours before starting the session, so there wasn't much left in the tank to burn anyway. Must remember to eat, if I'm going to work at this rate. My trainer bought me a Coke Zero to replenish my blood sugar level. It tasted terrible... but I perked right back up! The effect was almost instantaneous. Fuelled on sugar alone (artificial at that) I completed my training for the day without further difficulty.
Right. I'm not advocating tanking up with sugary drinks all the time. It worked surprisingly well in a pinch and saved me from my own stupidity, but the sugar either all burns to nothing, or stays inside and becomes fat which we're trying to avoid. Nothing beats having proper meals which become material to replace worn muscles, sinew and tissues after a workout.