Aging well is not just about living longer and looking youthful—it’s about sustaining the quality of life, energy levels, and physical health in your later decades. The sooner you introduce healthy habits and important lifestyle changes into your daily routine, the longer you will be able to enjoy your physical and mental well-being in later adulthood.
Multiple research indicates that physical activity, along with healthy eating and a regular sleep schedule, is one of the cornerstones of healthy aging. According to a 2020 study of 4,840 participants, 40+-year-old adults taking at least 8,000 steps per day had a significantly lower all-cause mortality risk compared to those who took just 4,000 daily steps. A review of 48 different studies, published in the journal Neurobiology of Aging, found that exercise improves both physical and cognitive health in older adults.
If you want to stay healthy for a longer period, you need to opt for a workout that offers you maximum longevity benefits.
Why REHIT is the best choice for aging well
REHIT offers a powerful alternative to the traditional way of exercising. This innovative training protocol emerged from the observation that just 2x short all-out sprints yielded fitness improvements similar to more or longer intervals. As a result, REHIT became a shortcut to enhanced fitness performance, boosted metabolism, and longevity.
The interest in sprint interval training emerged in the 1970’s. The concept of an all-out sprint was first developed by the Wingate Institute (hence its name—the Wingate sprint.) Wingate sprints showed tremendous results in improving the maximum oxygen uptake (VO2max) and anaerobic performance in both untrained adults and athletes compared to traditional training and HIIT protocols. However, the classic Wingate protocol consisted of 4 to 6 30-second sprints and was hard to perform even for advanced athletes.
As the scientists were looking to explain the beneficial effects of the all-out sprints, they discovered that they rapidly increased the body’s energy demand by about 100x compared to rest. The muscles couldn’t use the usual fuel sources such as glucose or fat, so they had to mobilize up to 25-30% of muscle glycogen (stored sugar) in response to this spike. The depletion of these emergency energy reserves serves as a signal of a ‘fight or flight’ situation for your brain. It triggers the release of key signaling molecules (AMPK and PGC-1a), telling your body it must get fitter and stronger.
The concept of REHIT was developed by sports scientists Niels Vollard, PhD, and Richard Metcalfe, PhD, in 2012. Researchers titrated sprint intervals until they found the minimal number which kicks off the metabolic changes. 2×20-second sprints work like flipping the switch of your metabolism and working longer or harder makes no difference.
The intensity is the driving force behind REHIT. During the 2×20-second all-out sprints, the rapid onset of glycogen depletion will induce metabolic changes—accelerated metabolism, mitochondrial biogenesis, and improved cardiovascular system.
The difference between HIIT and REHIT
Traditional high-intensity interval training (HIIT) consists of intervals from 30 seconds up to 2 minutes, with 1-2-minute rest between them. The intensity of HIIT workouts requires 75-90% of the target heart rate (THR) equivalent to Zone 4 training. This intensity is enough to effectively boost your VO2max and trigger an additional calorie burn during the excess post-exercise oxygen consumption (EPOC).
REHIT intervals are much shorter—10-20 seconds—with a longer 3-minute rest period in between 2 sprints. REHIT requires an all-out effort—90-100% THR equivalent to Zone 5 training. Despite the maximum intensity, most people can sustain this level of effort for 2×20-second sprints without discomfort.
REHIT on CAROL Bike is scientifically proven to deliver superior health and fitness benefits compared to regular cardio exercise in 90% less time.
REHIT and healthy aging
Intense bursts of physical activity catalyze important metabolic adaptations and promote rejuvenation on the cellular level. Regular 5-minute REHIT sessions bring you the following health benefits:
Improved cellular health
Mitochondria are the cell elements that produce energy out of glucose and fat. Mitochondrial dysfunction leads to accelerated aging and increased risk of type 2 diabetes, obesity, cardiovascular problems, and Alzheimer’s disease. When mitochondria can’t burn glucose efficiently, the pancreas releases more insulin contributing to insulin resistance and inflammatory responses.
The intense bursts of activity train mitochondria to burn glucose more effectively during and after REHIT training. Rapid depletion of muscle glycogen stimulates the pathways that develop new mitochondria and improves overall cellular health. REHIT can be an effective alternative to mitotherapy for mitochondria rejuvenation.
Cellular repair through autophagy
Autophagy (from the Greek “eating oneself”) is one of the body’s protective mechanisms that promotes cellular repair and rejuvenation. During this self-cleansing process, our body breaks down damaged components in cells and recycles them, defending cells against pathogens, toxins, and oxidative stress. Autophagy is effective in preventing age-related diseases, including Alzheimer’s, dementia, Parkinson’s, cancer, and infections. It improves metabolic efficiency, hormone regulation, brain function, and the immune system. Autophagy is a holistic approach that improves the performance of all bodily functions and promotes a healthy weight.
It was well known that autophagy can be activated after 60 minutes of traditional training. Recent research shows that acute high-intensity interval training stimulates cellular autophagy in a shorter time and a more distinct fashion.
Improved cardiovascular health
With age, the heart muscle weakens and arteries become stiffer. High blood pressure, atherosclerosis, heart disease, and stroke are the most typical diseases that may sometimes manifest even in middle age.
REHIT is the most time-effective workout to improve cardiovascular fitness—particularly, the maximum oxygen uptake (VO2max) which is directly correlated with heart health and longevity. After 8 weeks of regular CAROL Bike sessions, you will increase your VO2max by 12%, which is like turning your biological clock back by 10 years.
All-out intensity forces physiological adaptations resulting in more pumping capacity in the heart, more malleable arteries, better glycemic control, and improved diabetes-related cardiac impairments.
Regular REHIT training on CAROL improves all main blood levels: after 8 weeks, participants found out that their blood pressure was lowered by 5%, triglycerides decreased by 10%, good cholesterol (HDL) increased by 6%, and blood sugar was down by 2%.
Some scientists believe that low-volume high-intensity interval training such as REHIT should be the preferred training protocol for type 2 diabetes patients. At the end of an 8-week training on CAROL Bike, participants’ risk of type 2 diabetes was reduced by 62%—the same as after the Metformin treatment, a first-line medication for type 2 diabetes.
Massive calorie burn
Slow metabolism and obesity are often associated with the aging process and may cause aging-related diseases such as type 2 diabetes, heart disease and stroke, and osteoarthritis. REHIT accelerates metabolism for hours after training due to significant afterburn. Research by ACE (American Council on Exercise) shows you’ll burn more calories on a 15-minute CAROL Bike ride, than a 30-minute run.
Hormonal change
REHIT induces hormonal response regulating the levels of growth hormone, insulin, and ghrelin. Hormonal change facilitates fat loss, accelerates rejuvenation, and reduces stress levels.
Growth hormone and improved insulin sensitivity play a vital role in overall metabolic health and accelerate muscle growth. Some studies suggest that muscle mass is a more important indicator of the seniors’ health state and life expectancy than BMI. Preventing the age-related decline in muscle function leads to greater mobility and reduced falls and bone fractures. The decline in ghrelin after intense interval training suppresses the appetite and results in lower overall calorie intake.
Supramaximal exercise intensity triggers the release of endorphins—the natural painkillers and mood regulators. REHIT is a powerful tool to improve mental health, manage chronic stress, and get a good night’s sleep essential for healthy aging.
Anti-oxidant effect
When our body metabolizes oxygen, it creates unstable molecules called ‘free radicals’. Free radicals steal electrons from other molecules, causing damage to cell membranes, cellular proteins, lipids, and DNA. Antioxidants scavenge free radicals and prevent or reduce the damage caused by oxidation. The oxidative theory of aging suggests that high oxidative stress may cause premature aging and accelerate the development of cancer, atherosclerosis, and neurological diseases such as Alzheimer’s and Parkinson’s disease.
A 2021 research suggests that Sprint Interval Training is a more powerful protocol for upregulating antioxidant defenses than continuous endurance training. Regular REHIT sessions increase antioxidant system indicators, contributing to long-term cellular protection.
Ease of use
Last but not least REHIT benefit is its time efficiency—the training session lasts only 5 minutes. If you exercise regularly for 15 minutes per week, this is enough to reap the substantial benefits of training. When it comes to seniors, REHIT breaks another common barrier—the pain and discomfort they may feel during prolonged or too frequent training sessions.
The only way to perform REHIT properly
The only catch about REHIT is that this training protocol is hard to replicate outside of the lab. CAROL Bike is the only way to safely and effectively recreate REHIT, thanks to AI personalization that tailors the workout to you and helps you push to your limits during the sprints.
CAROL Bike is the only bike fully optimized for REHIT— making it simple, effective, and safe. It provides the shortest, most effective workouts suitable for any age and fitness level—while offering greater versatility and choice than most other smart bikes. This is particularly important when it comes to the anti-aging benefits of REHIT, CAROL Bike is the optimal option that ensures maximum benefits are being achieved.
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