The Norwegian 4x4 protocol involves 4 minutes of high intensity exercise (85%-95% max heart rate) followed by 3 minutes of lower intensity recovery, repeated four times.

“Warm up 4 min at 80-90% your max 4 min rest, keep moving Complete 4 rounds of this (4x4)”

“and that's that's what we'll typically prescribe to our patients is a 4x4 protocol of you know highest intensity sustained for 4 minutes followed by four minutes of recovery and and then repeat that four five six times”

“what we'll typically prescribe to our patients is a four by four protocol of you know highest intensity sustained for four minutes followed by four minutes of recovery and then repeat that four five six times”

“so we typically talk about a 4x4 four on four off right so so”

“The Norwegian 4x4 protocol is a great HIIT protocol for VO2 max training.”

“Norwegian 4x4 protocol improves VO2 max”

“One of the most effective, research-backed methods is the Norwegian 4x4 protocol—a proven approach that boosts VO2 max through structured high-intensity intervals”

“The Norwegian 4x4 Protocol for Increasing VO2 Max 4 minutes hard (85%-95% max heart rate ... these should be BRUTAL) Then 3 minutes lower intensity (similar to zone 1) Repeat 4x https://t.co/HNJwzbMMDb”

“One of the best protocols for improving VO2 max is the Norwegian 4x4 protocol - a 4-minute interval at the maximum intensity you can maintain the entire interval followed by 3 minutes of recovery - repeated four times.”

“I think the Norwegian 4x4 protocols probably one of the best out there um one of the best hit protocols out there for improving V2 Max”

“it really seems if you're really wanting to improve that cardiorespiratory Fitness that you have to do longer intervals so 3 to 5 minute intervals of just the maximum intensity that you can maintain for that 3 to 5 minutes and so a really good um and well studied a lot of evidence on the Norwegian 4x4 protocol”

“the Norwegian 4x4 protocol so this is 4 minutes of the highest intensity that you can do and then it's 3 minutes recovery so you're really going down to like light light exercise you want your heart rate to go down you want to sort of really give yourself some rest so that you can do it again so you repeat this four times that's why it's called 4x4 and this is one of the best protocols for improving V2 Max”

“I think one of the most evidencebased protocols if you look in the literature out there for improving cardiorespiratory Fitness is the Norwegian 4x4 protocol and this is where you do four minutes of the most in you maintain the intensity that you can for that entire 4 minutes so you don't want to like go out all out in the first minute do you want to be able to like pace yourself it's four minutes of you know high intensity exercise followed by 3 minutes of recovery and you do that four times”

“So that the Norwegian 4x4 was something that's practiced by these Norwegian skiing group and essentially they're doing 4 minutes interval and it's on a stationary bike and they're going as hard as they can and maintain for that four minutes. So they're not going all out because there's no way you can do that. But they're just going as hard as they can to maintain for that four minutes and then they have a threeminut recovery where they're going super super light. They're letting their heart rate come down to recover and then they go back at it again. So that's repeated four times. It's a 4x4.”

“I do think that we all should be aiming for it um in some shape or form um particularly if we're able to and knowing that the vigorous intensity exercise doesn't necessarily mean the Norwegian 4x4, although I still think I I'll still say I think we should be doing that type of hit um at least once a week to improve our cardiorespiratory fitness.”