I am not one to promote products but for the past few years I have been using MP3 files on my iPod for training indoors or on a spin bike at the gym.
There are 8 versions now and the rythmic music is different in each. The challenges are all based on perceived effort so they work for all fitness levels.
I highly recommend them and they have certainly kept me in shape over the winter months or when travelling on business.
They are only 15 dollars per session which makes them very affordable training.
Give them a try. www.cardiocoach.com
I am not affiliated other than as an avid customer.
