12 January 2016 Last updated at 09:50 GMT
In an era when an 80-120 hour week was seen as standard for junior doctors, they opted to not work beyond a  40-hour week.
Pay was another major issue at the heart of strike action in 1975. The rate of pay was reduced by about two-thirds after the first 44 hours of the week.
The junior doctors' strike began across England at 08:00 GMT on Tuesday 12 January 2016, with junior doctors only providing emergency care.
Weekend pay and concerns about safeguards to stop hospitals over-working doctors are the issues at stake.
The last major strike over pay and conditions by junior doctors was over 40 years ago in 1975.