Complex sentence: For a number of years he ran in masters events and his 200 meter run of 20.8 seconds in 1978 is still a current national record in the 35-39 age group.
Split into simpler sentences: For a number of years he ran in masters events with some success. His 200 meter run of 20.8 seconds in 1978 is still a current national record in the 35-39 age group.