Your average commuter’s route to work is more often than not interrupted by all manner of things: traffic, roundabouts, crossings, traffic lights etc. You can use this stop-start riding to your advantage.
One session that really works well is to try and pull away from each stop over-geared by one to two sprockets (i.e. it feels harder than normal). This means you have a really push to get going again, working in the same way as a gym session by focusing on pure leg strength.
If you imagine how many times you have to slow or stop on your daily commute, then you get an idea of how many efforts you would end up completing in this sort of short session.
The opposite of this session is to use a very small gear each time you accelerate (so you are under-geared). This forces you to increase your leg speed and helps you to improve your muscle activation (how quickly and efficiently your muscles fibers are firing).
Doing a combination of the over-geared and under-geared accelerations works on the two aspects of sprinting: leg speed and leg power. When you come to put these together in your weekend rides you should, over time, see an improvement in your sprinting ability.