I suggest not starting such a trip at 8:00AM.

As a student, I was usually able to arrange my schedule to avoid rush hour, but the school arranged a 3-day trip for us foreign students in the spring, and we were given tickets and were told to report to a certain Shinkansen that left at 9:00AM.

Standing on the platform at Nakano Station at 8:00AM, I watched several Chuo Line trains go past packed beyond capacity. From outside, the passengers looked as if they were flattened against the doors. Finally, I knew that I would have to catch the next train, no matter what.

Using my tote bag as a battering ram, I forced my way onto the train and ended up trapped in a "walk like an Egyptian" pose in the middle of the car. The good news was that I would definitely not fall over if the train rounded a curve quickly. I was pushed around as people got on and off at the intermediate stations, some of them frantically shouting, "Orosh'te kudasai!" and when the train finally pulled in at Tokyo Station, I flowed out with the rest of the humanity.

Yes, I made my train, but just barely. The doors closed behind me as I ran onto the first car. The train was already moving by the time I found my fellow students, who thought I had been left behind.

If you would like an adventure like that, start your journey at 8:00AM. If you have more flexibility, though, I would recommend going later in the day.