{"id":169940,"date":"2025-12-01T22:03:10","date_gmt":"2025-12-01T22:03:10","guid":{"rendered":"https:\/\/www.newsbeep.com\/ie\/169940\/"},"modified":"2025-12-01T22:03:10","modified_gmt":"2025-12-01T22:03:10","slug":"jessica-biel-43-is-obsessed-with-the-savage-4x4-workout-heres-why-its-so-effective","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ie\/169940\/","title":{"rendered":"Jessica Biel, 43, is obsessed with the savage 4×4 workout \u2013 here\u2019s why it\u2019s so effective"},"content":{"rendered":"

Jessica Biel is a \u2018total badass in the gym\u2019. Her PT Ben Bruno<\/a> said so \u2013 but just have a look at her workouts on his IG and you\u2019ll see for yourself. Strength training<\/a> is at the core of her routine, but in his latest post, Bruno revealed Biel has taken up the notoriously tough 4×4 workout. <\/p>\n

\u2018I recently introduced her to the \u2018Norwegian 4×4 protocol\u2019 on the Airdyne bike,\u2019 he wrote. \u2018And she\u2019s willingly done it five-six times in the last month, which is absolutely brutal and speaks to her work ethic.\u2019 <\/p>\n

The Norwegian 4×4 workout is a high-intensity cardio workout which includes 4 sets of 4-minute intervals where you push yourself to 85-95% of your maximum heart rate. It originates from the research of Professors Helgerud and Hoff<\/a>, who recommend it for both the general population and athletes. Biochemist Rhonda Patrick<\/a> described it on a recent podcast episode<\/a> as the \u201cgold standard\u201d for boosting cardiovascular fitness, and in one study, it led to a 13% improvement in VO2 max<\/a> over eight weeks, with three sessions per week. <\/p>\n

Boosting your VO2 max is one big benefit. The metric measures the maximum amount of oxygen your body can effectively use during exercise \u2013 the higher the number, the better. It\u2019s a reflection of how efficiently your heart, lungs and muscles work together to use oxygen, making workouts feel easier on your cardiovascular system. Its impact on VO2 max is why trainers say the 4×4 workout is more effective than a HIIT workout, since the 4-minute intervals are longer than standard HIIT intervals, meaning your heart reaches its full pumping capacity.<\/p>\n

As for the science supporting the 4×4 workout, a review<\/a> published in the Frontiers in Bioscience-Landmark found that higher VO2 max levels are associated with a reduced risk of mortality, while other research<\/a> shows that consistently doing the 4×4 can improve heart function in both the general population and sport-specific athletes, leading to a lower risk of cardiovascular disease, as well as improved health markers and increased longevity.<\/p>\n

How to do the Norwegian 4×4 workout<\/p>\n

Warm-up: Complete a low-intensity warm-up for 10 minutes. This could be a light cycle, jog or dynamic stretching<\/a>.<\/p>\n

Interval: Complete 4 minutes of a cardio exercise of choice, at 85-95% of your maximum heart rate. Biel cycles on an air bike, but this could also be running, swimming, rowing or high-intensity bodyweight exercises. <\/p>\n

Active recovery: Take 3 minutes rest of low-intensity activity like a slower, steadier cycle, brisk walking or jogging, taking your heart rate down to 60-70% of your max heart rate.<\/p>\n

Repeat: For a total of 4 high-intensity intervals and 4 rests.<\/p>\n

Cool down: Bring down your heart rate slowly, then stretch.<\/p>\n

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\u00a0As Women\u2019s Health UK\u2019s fitness director and a qualified Pilates and yoga instructor, Bridie Wilkins has been passionately reporting on exercise, health and nutrition since the start of her decade-long career in journalism. She secured her first role at Look Magazine, where her obsession with fitness began and she launched the magazine\u2019s health and fitness column, Look Fit, before going on to become Health and Fitness writer at HELLO!. Since, she has written for Stylist, Glamour, Cosmopolitan, Marie Claire, Elle, The Metro, Runner\u2019s World and Red.Now, she oversees all fitness content across womenshealthmag.com.uk<\/a> and the print magazine, spearheading leading cross-platform franchises, such as \u2018Fit At Any Age\u2019, where we showcase the women proving that age is no barrier to exercise. She has also represented the brand on BBC Radio London, plus various podcasts and Substacks \u2013 all with the aim to encourage more women to exercise and show them how.Outside of work, find her trying the latest Pilates studio, testing her VO2 max for fun (TY, Oura), or posting workouts on Instagram. \u00a0<\/p>\n