Time Travel via T-Shirt

We recently sorted through boxes of old race t-shirts from my childhood. The nostalgia is amplified as I now watch Jack bounce around the house in some of those old shirts. How do they fit him? Above: My first 10k road race was the Hyde Park Estates Run in 1981. Below: My flailing sprint to the finish on the Vanderbilt Mansion lawn.
Below: Jack reenacting the final 100 meters - with better form!
Below: Those socks were all the rage but I think my hair caused a slight aerodynamic problem.
Below: The starting line in 1981. The guy to the far right doing the sumo squat is wearing the same t-shirt. By the way, dude, etiquette dictates that you do not wear the race shirt the day of the race!
Was this really more than 30 years ago?