I've been feeling a strange feeling on my left knee, and I was thinking to buy a new bike in spring to keep my basic cardiorespiratory function. Today I visited a shop near my place to find one. It's for the first time in these 25 years for me to get a new bike, and I was very surprised to try some, as they're all too light and go smoothly. I bought a kind of 'cross bikes' called here, but I guess it is a Japanese English. Anyway, it is a hybrid type bike for both on- and off- roads for fitness. I wasted little time to take a trial ride today, in about 30km (18-19 miles), and I felt it was just as hard as a 10km jogging/running. I'm not a child, but it's nice to get a new toy to work out.