For years, the definition for a "good" cardio session was simple- the more intense, the better. From sprinting to spinning classes, and lately, the HIIT workout, the fitness culture has always emphasized intensity over endurance. But a quiet revolution is brewing—one that's rewriting old notions about endurance, recovery, and performance. It's referred to as Jeffing, and it's nothing new—but its science-supported advantages are catching on with a fresh generation of runners, recreational athletes, and even endurance experts who want to train smarter, not harder.Created by retired Olympian Jeff Galloway, Jeffing is a formal run-walk system intended to increase endurance, lower the threat of injury, and improve overall running performance. And yet, ironically, despite its effectiveness, the system is seen to feature prominently in marathon training programs, trail running, and even ultra-endurance events. As we redefine good cardio in an age more attentive to burnout and overtraining, Jeffing provides something revolutionary: permission to slow down—to go further.So why is this hybrid strategy catching on now? And might Jeffing be the sustainable cardio solution that HIIT was never designed to be?What Is Jeffing?Named after American Olympian Jeff Galloway, Jeffing is a run-walk approach intended to make running easier, more enjoyable, and surprisingly, more efficient. Galloway, who ran in the 1972 Olympics and has a personal best of 28 minutes in the 10k, came up with this technique to prevent runners from getting injured, keep their stamina, and actually enjoy the experience.Rather than forcing through tiredness until your posture breaks or you're put out by injury, Jeffing provides for walking breaks at intervals to reboot your muscles and your breathing—offering a perfect approach for newcomers and experienced runners alike.Let's dispel the myth first: Jeffing does not equate to "quitting" running or compromising on a less efficient workout. Actually, walk-run intervals are an established training mechanism in endurance sports. Trail runners, ultramarathoners, and even top athletes make regular use of walk breaks—particularly when they are running long distances or tackling hills.No matter if you're training couch to 5K or just training for the next marathon personal record, Jeffing allows you to control heart rate, fine-tune respiratory patterns, and alleviate joint impact but still achieve cardiovascular and muscle training benefits. Intervals at your service , smarter and easier.One study, reported in the Journal of Science and Medicine in Sport, compared finishers of marathons who employed the run-walk technique with those who ran non-stop. The outcome was dramatic: Jeffers finished the 26.2-mile marathon in essentially the same amount of time as conventional runners (times were 4:14–4:34 for Jeffers vs. 4:07–4:34 for runners).But here's the kicker—Jeffers reported significantly less muscle pain and fatigue afterward. For anyone concerned about injury prevention or longevity in their running journey, this benefit is hard to ignore.How Jeffing Works?Running for long durations is demoralizing—particularly for beginners. The thought of hammering the road continuously for 30, 60, or even 90 minutes is daunting to most. Jeffing eliminates that mental block by incorporating scheduled rest. If your mind is aware that a break is only minutes away, you are more likely to remain excited and plow through the exertion.Physiologically, walk breaks permit muscles to recover without sacrificing forward motion, decrease total fatigue, and prevent the sort of overuse injuries that befall so many runners. The tactic also provides your cardiovascular system with a break to readjust, enabling more effective energy utilization over greater distances.How to Start Jeffing?Starting with Jeffing is remarkably easy—and highly customizable. You can base your run-walk intervals on either time or distance, depending on your goals and fitness level. Here are some popular beginner-friendly examples:Run 2 minutes, walk 30 secondsRun 1 km, walk 1 minuteRun 4 minutes, walk 1 minuteRun 400m, walk 100mWhether you use a running watch with interval notices or just make timers on your phone, consistency is the rule. And one more thing: Don't delay walking until you're exhausted. Integrate walk breaks from the very start of your exercise to get the maximum benefit.One of the standout features of Jeffing is its adaptability. Beginners can use it to gradually build endurance, reducing the risk of burnout or discouragement. For advanced runners, Jeffing is a strategic way to tackle longer distances, increase weekly mileage, or recover between high-intensity sessions.For instance, a person preparing to run a marathon may begin with a 1-minute run/1-minute walk plan, gradually increasing longer run intervals in the process. Ultimately, you might work towards running most of the race while continuing to include strategic walks on hills or at aid stations.Jeffing vs. HIITSo how does Jeffing compare to high-octane routines such as HIIT? The reality is, they're not competing. HIIT is great at increasing anaerobic capacity and metabolic rate in short, intense bursts. Jeffing, conversely, prioritizes endurance, joint health, and mental sustainability.Actually, most runners find that a hybrid system is beneficial—HIIT for brief, intense workouts during the week, and Jeffing for weekend long runs that build endurance and cardiovascular capacity. Whether you're preparing for your first 5K or your fifth ultra-marathon, Jeffing is a science-supported, accessible, and fun way to achieve success.