The Florida-based light-heavyweight doesn't much like the cold. But stepping into a cage with six-foot-five Swede Alexander (The Mauler) Gustafsson doesn't faze him one bit.
"No point in being like all high-strung and stiff like that," said a relaxed Johnson. "That gets you nowhere. That's wasted energy."
The two fighters meet Saturday on a televised UFC card at the 30,000-plus Tele2 Arena with a title shot on the line.
Gustafsson (16-2) is ranked No. 1 among 205-pound contenders and working his way to a rematch with champion Jon (Bones) Jones, whom he pushed for five gruelling rounds in Toronto before losing a close five-round decision at UFC 165 in September 2013.
Johnson (18-4) is ranked third among light-heavyweights, a well-rounded and hard-hitting fighter now campaigning in his third weight class.
The UFC is billing the card as just its second "major stadium event" and the first in Europe. UFC 129 drew 55,000-plus to Toronto's Rogers Centre in April 2011 to see then-welterweight champion Georges St-Pierre defeat Jake Shields.
The Tele2 Arena, which features a retractable roof, is normally home to the Hammarby IF and Djurgardens soccer teams.
"It's just huge," said Johnson.
"it's going to be massive," added Gustafsson. It's going to be packed."
The six-foot-two Johnson has won eight straight, knocking out Antonio Rogerio Nogueira last time out. Gustafsson defeated Jimi Manuwa in March for his seventh victory in his last eight fights.
There has been plenty of respect between the two fighters in advance.
"I think he's awesome," Johnson said of the big Swede. "He seems like a good guy. Great fighter, obviously. A lot of experience ... I'm just honoured to be able to fight him."
"First of all he's a very humble person," Gustafsson said of Johnson. "And a great fighter. A lot of power. Heavy hands. So it's really going to be a test for me Saturday but I've done my homework and I'm ready. I'm going to solve the problem."
Johnson, who walks around these days at 230 to 235 pounds, had trouble making weight in the past. He would cut from 210 pounds to 170 to make welterweight.
Still he has no regrets about those past struggles.
"Trying to make 170 was tough," he said, not surprisingly. "But if I hadn't fought at 170 people might not know who I am right now if I hadn't made that sacrifice and did the things I did at 170."
"It was crazy," he said of the weight cut. "I don't recommend that for anybody."
Johnson, 30, had been punishing his body for a while. A former junior college wrestling champion, he competed at 174 and 184 pounds while at Lassen Community College in California.
Thanks to a knee issue, the 28-year-old Gustafsson has spent just four minutes 18 seconds in the cage since meeting Jones in Toronto. He's had a lot of time to think about his fight with the champion, a bout he still thinks he won — as does Johnson.
In Saturday's co-main event, 44-year-old Dan Henderson (30-12) returns to middleweight to face No. 8 Gegard Mousasi (35-5-2).
Also on the card, No. 5 light-heavyweight contender Phil (Mr. Wonderful) Davis (13-2 with one no contest) takes on No. 7 Ryan (Darth) Bader (19-4).
Saturday's card features fighters from 13 countries.
"It's growing fast," Gustafsson said of MMA. "It's one of the biggest sports right now in Sweden."
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