Whilst there are still western influences with things like Starbucks & McDonalds, in general all of the fast food outlets and convenience stores sell mainly Japanese foods - none of which are the heavy, calorie packed, grease or gravy soaked meals you would find your local pub or fish & chip shop selling in England.
As a result, the vast majority of the population enjoy the benefits of eating light, fresh foods on a daily basis. Now, combine this with the other major factor - everyone is constantly on the move!
Tokyo boasts the biggest population of any city in the world, and with that comes an incredibly busy, fast moving lifestyle. If you stand still it will swallow you up!
The people work long hours, and like most big cities around the world, traffic is awful and the roads are reserved mainly for buses & taxis. This means the daily commute involves walking, running, cycling or the tube.
There could be many reasons why it is so loved as a sport in Japan and in Tokyo - perhaps it is because it reflects the hard working nature of the people and the culture, or the low-cost factor of running in a city where the cost of living is so high.
It could be the Tokyo Marathon, which allows the city to put itself in the worldwide spotlight each year and helps create role models for the young Japanese, or simply the health benefits and getting some freedom in such an overcrowded, hectic environment.
As with Kenya, much can be speculated as to why and how one country can love the sport and excel at it so much more than any other country - the answer obviously is much harder to pinpoint and consists of numerous factors.
The day I arrived just so happened to be the day of the 2013 Tokyo Marathon, and by the sheer volume of spectators, you can see there is a real love of the sport.
I have been fortunate to run in twenty four different countries in six continents, and I can honestly say I saw more runners in Tokyo than anywhere else I have been, including Kenya!
All standards, from packs of 8-10 running tempo sessions, to the elderly joggers being overtaken by walkers. Running is ingrained in the daily routine and the way of life in Japan.
Surprisingly, unlike London which despite it's huge population and gridlocked transport networks has large public parks like Hyde, Regents or Hampstead Heath in which to escape, Tokyo is very short on space to stretch your legs.
Inspired from watching the world's elite complete the 26.2 I used my map to track down some of these parks to run in, despite temperatures down in single figures. However, I quickly found out (on numerous occasions), that running is prohibited in almost all of these parks!
Almost instantly upon entry and opening my legs, I was greeted with shouts of "STOP!" or whistles from Park Officers in uniform bearing their famous red sticks (that look light light sabres!).
After a horrible 60 minute run consisting of countless pedestrian crossings and traffic lights, I showered and decided research was required for my intended 10 mile run on Day 2!
In the pouring, sodden rain, I headed for the Imperial Palace, which my research reliably informed me was the running capital of Tokyo. Upon exiting the tube station and jogging the 300 yards to so to the Palace, I was greeted with probably more runners than I would see in a year in my hometown of Woodbridge in Suffolk!
Never before have I seen so many shiny bright coloured tracksuits, fluorescent shoes, ear muffs, elaborate headphones and handheld water bottles!
Surrounding the Imperial Palace and the Gardens/Moat is a 5k loop. How do I know it was 5k? Because there are distance markers on the pavement/sidewalk telling you so!
Tokyo has a strange climate in that Winter is very dry, but very cold, whilst Summer is very hot but very wet. The best times to visit are March-April when the flowers and the trees begin to bloom. However, I was here in February and whilst it was cold (around 7-10 degrees C), it was still very pleasant.
You are absolutely fine to run with your headphones, and Tokyo is one of the safest places I have been, so you will be fine to run with your iPhone or MP3 player and Garmin. Still be careful to be sensible though when running at night, and maybe take a business card for your hotel/hostel and some cash in case you get lost - far easier than asking for directions in Japanese!
For anyone lucky enough to visit Tokyo - don't be put off but anything I have said - yes there are not too many places to run, and even fewer open parks to stretch your legs. However, being part of the Imperial Palace daily swarm of runners, which so typifies everything about this incredible city, is an experience you cannot and must not miss out on!
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Summary - 5k Route
Start - Either Takebashi or Kudanshita Metro Stations
(Both to the north entrance of Imperial Palace entrance)
Simply follow the walkway as it circles the perimeter of the Imperial Palace Gardens.
The north side of the Palace is far higher than the South, so depending on how you want your run, keeping the moat to your left hand side will mean the first half of your run is downhill and the second uphill.
Obviously if you want to have the first half of your run uphill, with a downhill finish, you will need to get off the metro at one of the southern stops, so try Sakuradamon or Nagatacho.
The metro stations are all coded (U3, S2 etc) so don't worry about having to remember of translate some of the long Japanese names!
Use the distance markers on the gold plaques to establish the distance, and do as many loops of the 5k as you feel up for!
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I have written over 30 other city guides, including Sydney, Rio de Janeiro, Paris and San Francisco, which you can find using the links on the right of the page!