It's only February and already Roger Federer, Serena Williams and Tom Brady have shown that the youngsters don't have a monopoly on vim and vigor.
Sometimes age and experience can trump youthful exuberance.
Guay hadn't won for almost three years when he became skiing's oldest world champion with victory in the super-G at glitzy St. Moritz Wednesday.
The 2011 downhill world champion edged out Olympic champion Kjetil Jansrud, 31, with fellow Canadian Manuel Osborne-Paradis grabbing third on his 33rd birthday.
Guay's achievement comes three days after 39-year-old quarterback Brady steered the New England Patriots to a remarkable Super Bowl victory after trailing the Atlanta Falcons 28-3 in the third quarter.
It was Brady's fifth Super Bowl title, all with the Patriots, coming 15 years after his first.
In both games Brady was named Most Valuable Player.
Federer is another 35-year-old still performing at the top of his game.
The Swiss won a men's record 18th grand slam singles title last month when he beat Spain's Rafael Nadal in a thrilling five-set Australian Open final.
It was Federer's first grand slam title since Wimbledon in 2012 and first final since the 2015 US Open.
Also in Melbourne, Serena Williams struck a blow for "older" women with a record 23rd grand slam singles title at -- yep, 35.
Bucking the trend is Tiger Woods, whose comeback from injury at the age of 41 suffered a setback in Dubai last week.
Playing in only his second full-field event for 17 months to rehab from back surgery, Woods pulled out of the European Tour's Dubai Desert Classic after round one, citing "back spasms."
Fortunately, Sergio Garcia was able to fly the veterans' flag with victory in Dubai at the age of 37.
However, the Spaniard's win was shortlived respite for the old guard.
Japan's 24-year-old Hideki Matsuyama won the Phoenix Open on the PGA Tour later that day to continue his duel with Justin Thomas, 23, as golf's hottest property.
In football, 44-year-old Egypt goalkeeper Essam El-Hadary also made headlines when he saved two penalties to take his side into the Africa Cup of Nations final earlier this month.
However, El-Hadary was denied a fairytale finish when Cameroon lifted the trophy with a 2-1 win in Libreville.
Back to skiing, and the 32-year-old Lindsey Vonn is still the one to beat on the women's speed events. The American failed to finish in Tuesday's super-G at the World Championships in St. Moritz but is hot favorite for the downhill title
Vonn, the 2010 Olympic downhill champion, won her 77th World Cup race in January, nine weeks after recovering from a broken arm and nerve-damaged right hand.
She is the second most successful skier of all time, behind Sweden's Ingemar Stenmark with 86 World Cup wins.
The youth are the future. The oldies, it seems, are the present.