Palmer managed just 11 goals in 34 appearances across all competitions last term as a recurring groin issue, described by sources as complex and requiring day-to-day management, disrupted his campaign and ultimately cost him a place in England's World Cup squad this summer.
Alonso, in his first pre-season as Chelsea manager, said Palmer had used the enforced break to reset both physically and mentally.
"Cole is determined to enjoy his football," Alonso said. "He wants to be fit, he wants to feel healthy. He wants to have a good connection with the players around him.
"We have this goal. If we are able to reach him and he feels that flow in the game and connects well with the players, I'm sure his level is top, top class, world class, and that he will have a great season."
Asked directly whether last season's fitness problems have been resolved, Alonso pointed to the process Palmer has been through.
"I've seen that. I think that sometimes you need to go through a moment with an injury or whatever to learn from that. Cole has gone through a difficult period with an injury and now he's working really hard to have the prevention to not feel those symptoms back. Since the first day, he's been working really hard to avoid that."
Palmer was a prominent figure throughout pre-season under Alonso and is expected to start when Chelsea open their Premier League campaign away at Fulham on Monday night.
Elsewhere in Alonso's squad update, new signing Danny Welbeck will be assessed this weekend after carrying a knock in recent days, though the Spaniard said he expects the former Brighton forward to be fit for Craven Cottage. Alonso would not confirm whether Mykhailo Mudryk, who recently returned to action following the lifting of his anti-doping ban, will be involved, with sources close to the club suggesting a loan exit could still be on the cards for the Ukrainian.
"We will see," Alonso said when asked if Mudryk would be in the squad. "We don't have to rush on decisions. At the right time, we will take that decision."