Whether your use an online journal or the old fashion pen and paper, it is the one thing I have done faithfully for the past two years. And with great success. Old fashion journal - has my work schedule, work notes, workout program for the day, food journal, workout results, great quotes, etc.
The best thing! It is all in one place and easy to find. The coolest thing I have learned from this is finding out how much I have improved on cardio and lifting. Where a lift program 6 weeks ago had my heart in a high range for 30 mins. - it is now only in that range for 10 mins. Up the weights