I do, however, start to get sick. What that means is that I start to feel extra tired and hungry, and I stop making any progress in the gym.

I generally notice when this starts to happen, and I adjust my routine accordingly. This time, however, I didn't catch it in time. I went to the gym one extra day before realizing that I was hitting a wall, and I'm now paying the price. I'm not sick, I'm just feeling more tired than usual.

The only cure is to take extra Vitamin C and avoid the gym for about a week. By then, I'll have recovered.