Andrew Botham, Aslef Union say they're unhappy at plans by East Midlands Trains to cut the amount of money it, and staff, pay into their pension scheme.
The company says it'll save employees around £500 pound a year in contributions.
Unions argue it's being done to boost profits for East Midlands Trains parent company Stagecoach.
East Midlands Trains says it will aim to provide as many seats as possible for people travelling to the Olympic Games.
Communications have broken down between East Midlands Trains and ASLEF, as the union confirms train-drivers will strike during the Olympics
Train drivers are staging three days of strikes during the Olympics in a row over pensions.