Connect with us


To ice or not to ice? Icing promotes muscle regeneration after mild injury

Cumulative research by a multi-institutional Japanese research collaboration reveals that ‘to ice or not to ice’ may depend on the degree of muscle injury.



Applying ice to a muscle injury is a widespread first-aid treatment, but exactly what effect does this have on the muscle regeneration and does it really help? Cumulative research by a multi-institutional Japanese research collaboration reveals that ‘to ice or not to ice’ may depend on the degree of muscle injury.

In their latest research, the group consisting of Associate Professor ARAKAWA Takamitsu and Master’s student NAGATA Itsuki (from Kobe University’s Graduate School of Health Sciences), and Assistant Professor KAWASHIMA Masato (Kawasaki University of Medical Welfare) et al. have shown that applying ice to muscle damage in a small percentage of muscle fibers in rats promotes muscle regeneration. This is believed to be the first study in the world to show benefits of icing on muscle repair. In conjunction with their previous study on serious muscle injuries (‘Icing muscle injuries may delay recovery’), it is hoped that these results can be used as a basis for more accurate guidelines on whether or not to ice such injuries.

These research findings were first reported in the American Journal of Physiology-Regulatory, Integrative and Comparative Physiology on March 6, 2023.

Main Points

  • The experiments showed that applying ice after a mild muscle injury promotes muscle regeneration.
  • This is believed to be the first time in the world that a study has shown a positive effect of icing on muscle regeneration.
  • The researchers showed that the extent of the injury may have a greater impact on the effectiveness of icing than the method or timing employed.
  • The findings of this ongoing research will lead to the spread of more accurate information on the effects of icing throughout hospitals, and in the realms of sports and physical education.

‘RICE treatment’ is a common approach for treating the acute phase of sports injuries. This acronym stands for Rest, Ice, Compression and Elevation and it is also often used in physical education in schools and even clinical settings. There are a variety of subsequent steps that can be taken to treat the injury afterwards, yet opinions vary as to whether or not icing should be applied. However, there is a lack of evidence on the benefits of icing.

The current research team has conducted many experiments to investigate the effectiveness of icing, which led them to publish their previous findings (‘Icing muscle injuries may delay recovery’ ). However, no previous animal experiments have indicated that icing promotes muscle regeneration.

In this study, the researchers focused on altering the severity of the muscle injury in the experiments. The reasoning behind this was that the majority of sports-related muscle injuries are limited; in other words less than 10% of the overall number of muscle fibers (myofibers) are damaged and necrotized. However, all animal experiments up until now had looked at more serious injuries where over 20% of the myofibers were damaged.

Thus, the team devised an animal model for mild muscle injuries, and experimented with applying ice after injury using a similar method as before.

After the animal was anaesthetized, the muscle was exposed and clamped between forceps to induce injury. In their previous experiments, the researchers attached a 500g weight to the forceps, which induced an injury that affected 20% of the total number of fibers in the muscle. In the present study, they tried attaching a 250g weight to the forceps and demonstrated that this could be used to consistently injure 4% of the fibers (Figure 1). This is similar to the degree of injury that often occurs after sports activities such as vigorous exercise or long-distance marathon running.

Icing was carried out by placing polyethylene bags of ice on surface of the skin over three 30-minute sessions per day, with each session being 1.5 hours apart. This was continued until two days after injury for a total of 9 icing sessions (i.e. immediately after injury = 3 sessions, 1 day after injury = 3 sessions, 2 days after injury = 3 sessions). The icing method was the same as in the previously reported study (‘Icing muscle injuries may delay recovery’).

Observations of muscles that were regenerating in the icing group and no-icing group 2 weeks after injury revealed significant differences in the size of regenerating fibers in cross-sections (Figure 2). In other words, this demonstrated the possibility that skeletal muscle regeneration is promoted by icing.

Macrophages are immune cells that orchestrate the reparative process of injured muscle. Pro-inflammatory macrophages accumulate in the damaged site soon after injury occurs, however they express an inducible nitric oxide synthase (iNOS), which has a disadvantageous side-effect of expanding the injury’s sizeThe results of this team’s experiments revealed that icing after mild muscle injury reduces the accumulation of iNOS-expressing pro-inflammatory macrophagesBy causing this phenomenon, icing prevents the expansion of muscle injury size.

In other words, icing attenuates the recruitment of pro-inflammatory macrophages in the injury site. This was also reported in their previous study (‘Icing muscle injuries may delay recovery’), demonstrating that this is an effect caused by icing regardless of whether the muscle injury is serious or mild. In the previous study, icing was found to delay the regeneration of muscle after a serious injury that destroyed many fibers because the pro-inflammatory macrophages were unable to sufficiently phagocytose (*5) the injured muscle. In contrast to this, the current study shows that icing has a positive effect when the muscle injury is mild because it prevents the secondary expansion of the muscle injury caused by the pro-inflammatory macrophages. It suggests that this particular effect of icing is connected to the promotion of muscle regeneration.

Icing has been used in the treatment of muscle injuries for a long time, however the positive effects of icing had yet to be elucidated until now. This study has shown that icing can promote muscle regeneration when used to treat commonly-occurring mild muscle injuries.

However, this does not mean that icing is effective for all types or degree of muscle injury. The researchers aim to further elucidate and raise awareness of this. For example, the group’s previous study showed that icing actually inhibited regeneration in cases of serious muscle injury. In addition, the term ‘muscle injury’ also includes extremely minute injuries that have yet to be observed through the team’s animal experiments, so it is still unclear as to what effect icing has on the repair from such microtraumas.

The researchers’ next challenge is to determine the extent of muscle injury up to which icing is appropriate. By building upon their previous investigations, they aim to contribute towards guidelines that will enable people in sports and clinical rehabilitation to make accurate judgements about whether or not to ice an injury.

Zest Magazine accepts contributions promoting everything about living the good life (and how to make this so). C'mon, give us a yell.


People who are in good shape take fewer mental-health related medication

Being in good physical shape helps all age groups and both genders. However, some people get greater benefits from exercise and being in good physical shape than others.



“We find that people who are in better shape fill fewer prescriptions for anxiety and depression medications,” says Linda Ernstsen, the senior author of the article and an associate professor from the Department of Public Health and Nursing at the Norwegian University of Science and Technology (NTNU).

The research group based its work on the  Trøndelag Health Study (HUNT). Since 1984, 250,000 Trøndelag residents have voluntarily contributed their health data to this comprehensive research project. The data are available to researchers, who can use the data to estimate people’s fitness levels, among other things.

The figures were taken from the third data collection round, called HUNT3, which was conducted from 2006 to 2008.

The research group compared the data from HUNT3 with data from the Norwegian Prescribed Drug Registry, which provides an overview of medications that have been dispensed in Norway.

Reduces the need for medication

“Being in better physical shape appears to reduce the need for anxiolytic drugs and antidepressants,” Ernstsen said.

In a previous study, Ernstsen and her co-authors found that people who were in good physical shape during the second HUNT study had a lower prevalence of depressive symptoms when they were participants in HUNT3 ten years later. However, at the time, the researchers found no correlation between good physical shape and anxiety.

But the new study design, which allows the researchers to look at what kinds of medication HUNT3 participants obtained from pharmacies as late as 2018, allowed the researchers to find the correlation.

However, the study does have a theoretical catch. The researchers can only see what kinds of medication were dispensed to people by pharmacies. They cannot see whether people actually took the medication — there’s no way to monitor people at their medicine cabinets.

“Nevertheless, there is reason to believe that people who are prescribed medication have more symptoms than those who do not see a doctor,” according to first author Audun Havnen, an associate professor at the Department of Psychology at NTNU.

Greatest effect for men and young people

Being in good physical shape helps all age groups and both genders. However, some people get greater benefits from exercise and being in good physical shape than others.

“We find that men experience a greater effect from exercise than women. The correlations are also less clear for the elderly,” Ernstsen says.

But that doesn’t mean that it isn’t important for women and the elderly to exercise.

What came first?

We can, of course, ask what triggers what. Is it actually the case that good physical health helps prevent anxiety and depression? Or is it the case that people who suffer from anxiety and depression exercise less and are therefore in poorer shape?

In order to not include anyone who was already experiencing anxiety or depression at the start of the study, the researchers excluded anyone who had filled prescriptions for these conditions before participating in HUNT3, as well as for three months afterwards.

“We also adjusted for symptoms of anxiety and depression in statistical analyses. To the extent that the figures can be believed, we also feel fairly confident that we started with a relatively anxiety and depression-free cohort in HUNT3,” Ernstsen said.

In other words, the subjects were unlikely to have suffered from anxiety or depression beforehand.

Unfortunately there are no shortcuts for people who can’t be bothered to exercise. We simply have to get started — unless we decide to give up. But is there really no other alternative?

“The results indicate that you can achieve a protective effect by improving your physical shape from poor to moderate, so any activity is beneficial,”  Havnen says.

You should be physically active in a way that leaves you breathless and sweaty if you want to improve or maintain your physical condition. The Norwegian health authorities recommend that adults be physically active for at least 150 to 300 minutes at moderate intensity each week.

However, one option for people who are short on time is to aim for 75 minutes of high-intensity training each week or a combination of moderate and high-intensity training.

“Research reinforces the finding that each minute of physical activity counts,” Ernstsen said.

Authored by Audun Havnen, Ekaterina Zotcheva, Ottar Bjerkeset, Xuemei Sui, and Linda Ernstsen, “Cardiorespiratory fitness and incident use of anxiolytics and antidepressants in adults. A linkage study between HUNT and the Norwegian Prescription Database” appeared in the Journal of Affective Disorders.

Continue Reading


The magic number: How many days a week you need to exercise to see real benefit

If it is not possible to have 20 minutes a day for exercise, even five minutes a day makes a difference for fitness and health.



Want the health benefits of exercising, but aren’t too keen on pounding the pavement or pumping iron every day?

Edith Cowan University (ECU) may be able to clarify how many times per week you need to exercise to make it worth your while.

new study saw participants perform a single three-second, maximum-effort eccentric bicep contraction — similar to slowly lowering a heavy dumbbell, from a bent arm to a straight arm.

Previous ECU research showed this can significantly improve muscle strength when it’s performed daily for five days a week (Monday – Friday), for four weeks.

Participants in the new study were split into two groups, with the first group performing a single three-second contraction two days per week, and the other performing the same exercise on three days per week.

After four weeks, researchers compared the participants’ bicep strength.

Those who performed the exercise two-days per week saw no significant changes, however the three-day group saw small but significant increases in concentric strength (2.5 per cent) and eccentric strength (3.9 per cent).

Study lead Professor Ken Nosaka said the results helped to further improve our understanding of how our body responds to exercise — and how people can then put that knowledge to good use.

“Our previous work has shown regular, shorter exercise is more beneficial than a one or two big training sessions in a week,” Professor Nosaka said. “Now, we have a clearer idea of where the tipping point is where you start to see meaningful benefits from such a minimal exercise. These new results suggest at least three days a week are required, at least for the single three-second eccentric contraction training.”

Three is good… but five is better

While the findings showed three days per week will have an impact, finding the willpower to put in a couple of extra days of exercise per week will produce better results.

The previous study’s participants who performed the exercise five days a week saw greater improvements in strength — more than 10% increases — than the three-day group.

However, Professor Nosaka stressed this didn’t mean exercising every day would improve results even further.

“Muscle adaptations occur when we are resting, so muscles need rest to improve their strength and their muscle mass,” he said. “It should be noted that the exercise was only three seconds, so the rest between exercises in the study was close to 28,800 times more than the exercise time. But muscles do appear to like to be stimulated more frequently, especially for the small volume of muscle strengthening exercise.”

Applying it to real life

Professor Nosaka said more research was needed to see if the study’s findings apply to other types and volumes of exercise.

“Muscles enjoying frequent stimulation may not necessarily be the case for a greater volume of aerobic exercise to improve cardiovascular function, or muscle strengthening exercise such as working out at a gym,” he said.

“However, it may be that exercising once a week for 2 hours is less effective than exercising every day for 20 minutes.

“If it is not possible to have 20 minutes a day for exercise, even five minutes a day makes a difference for fitness and health.

“Of course, more studies are needed to confirm this, but our recent studies show the importance of accumulating small amount of exercise as frequently as possible in a week.

“It is important to note that even a very small amount of exercise can make a difference to our body, if it is performed regularly.”

‘Weekly minimum frequency of one maximal eccentric contraction to increase muscle strength of the elbow flexors’ was published in the European Journal of Applied Physiology.

Continue Reading


Awaken Gym celebrates first anniversary

Headed by Culver Padilla, co-founder of the gym and a personal trainer to celebrities, the coaches in this Pasig-based fitness center subscribe to the belief that working out should not leave you sore and aching. Instead, post-workout sessions at Awaken will leave you satisfied, energized and ready to take on the challenges of the day.



No pain, no gain? Not if you ask the trainers of Awaken Gym. “No pain? More gain!”

Headed by Culver Padilla, co-founder of the gym and a personal trainer to celebrities, the coaches in this Pasig-based fitness center subscribe to the belief that working out should not leave you sore and aching. Instead, post-workout sessions at Awaken will leave you satisfied, energized and ready to take on the challenges of the day.

“Our workouts are challenging but not overwhelming which makes it very sustainable,” explained Coach Culver. “Pain is a sign that your muscles are either not used to the workout or it exceeded its capacity. By working with our highly trained professionals here at Awaken, we will start with an assessment so we curate the routine according to your body’s needs and current capacity, with just enough intensity that would still allow you to function normally as you go about your daily lives.”

This mindset and practice towards working out is what makes the fitness lifestyle sustainable, he added. And it does not start and stop with physical exercises. Awaken Gym prides itself in the holistic development of its members, making sure eating and sleeping habits are reformed, if not improved altogether.

“Rest and recovery are just as important as working out. Exercise creates microscopic tears in your muscle tissue. But during rest, cells called fibroblasts repair it. These help the tissue heal and grow, resulting in stronger muscles,” said Coach Culver. Awaken is one of the few, if not the only, gyms offering red light therapy—part of its NSDR method or the practice of Non-Sleep Deep Rest, he explained. It puts the body into a deep relaxation state to allow it to reset and go back to recovery mode after triggering the fight-or-flight response during the workout, Coach Culver added.

Home away from home

The F2 Logistics Cargo Movers, a perennial title contender in the pro volleyball scene, are proud to call the Awaken Gym their second home. Sonny Montalvo, who doubles as the team and the gym’s strength and conditioning coach, leads the weekly training of the athletes to ensure that they are in their best form to compete.


F2 Logistics Cargo Movers training at Awaken

“While Awaken serves as a home to those looking to improve their fitness lifestyle, this gym is also a home to elite athletes who wish to train for high-level competitions,” Coach Sonny said. “Since F2 Logistics started training here at Awaken, the team got back to the podium.”

“Thank you Awaken for being our second home and providing us a conducive space to better ourselves,” said Cha Cruz, outside hitter for F2 Logistics. “I’m in the best shape of my life so far and I’m looking forward to getting stronger and better. The people at Awaken are so welcoming and helpful, and I’m very grateful that they do everything they can to support my team and myself,” setter Iris Tolenada added.

Something for everyone

Effectivity and variety are the bread and butter of Awaken Gym. Coach Culver has made it a point for himself and the other coaches to continuously study the latest developments in physical fitness, training, and the like, and apply those in their gym. Paraphrasing Bruce Lee, Coach Culver said of this practice, “Research, absorb what is useful, discard what is unnecessary, and add what works for you.”

One of the most effective routines for the gym’s members is the Functional Training Fundamentals (FTF). “You might just be carrying grocery bags up the stairs and afterwards you’re already gasping for breath. That’s what FTF works on: the muscles you use and the movements you do everyday to improve overall health and lifestyle. These are workouts that actually make sense, and by being consistent with it you also get a bonus of above average physique,” Coach Culver said.

Coach Sonny added that variety is important for non-athletes looking to get fit. Without variety, people would tend to get bored doing the same things over and over. By applying new learnings and strategies, as well as getting the latest certifications, the coaches of Awaken Gym have expanded their offerings to include the following, aside from Strength and Conditioning and FTF:

  • Animal Flow workout—ground-based movement designed to improve strength, flexibility, mobility, and coordination;
  • Calisthenics; Athletic Performance; Biomechanics Training;
  • High Intensity Interval Training; Circuit training; Spartan training;
  • Therapy, including but not limited to: sports taping, dry needling, physical therapy, myofascial release, and the like;
  • Kids workout; Corporate team building;
  • And others, like meal prep, merchandise, as well as a meeting and small event venue.

Kids workout with Coach Anjo Resurreccion

Hendrick Young, who has been a member of Awaken for the past year, testified to the holistic development that the gym works towards. “One of the greatest things I learned from Awaken is that working out is a lifestyle, not just an activity we do a few times a week. Awaken also helped me to see that nurturing and developing mental fitness is just as important as physical fitness.”

He added, “When I joined Awaken, I expected to become a member of a gym but I ended up being a part of one big family.”

Dr. Jeffrey Ang, who also started on his fitness journey nearly a year ago, attested to the welcoming atmosphere that Awaken exudes. He shared, “What drew me in is the heart and soul of Awaken—the coaches and staff. I have always had a hard time every time I do trials in a gym. I am fortunate enough to have the privilege to train with one of the best coaches in the country, Culver. He was able to push me and my boundaries to the limit, like I was able to go outside of the box, learn and develop myself without compromising each other’s individuality.”

Dr. Ang added, “The community is one of the factors that really sold it for me. From the staff to the different clients that I met, I never felt like I was someone less. The people all understood that we are in this together—a collective of people helping and pushing each other for the betterment of each individual.”

For those interested, visit its Instagram page @awakengymofficial for more details.

Continue Reading

Like Us On Facebook

Facebook Pagelike Widget

Most Popular

Copyright ©FRINGE PUBLISHING. All rights reserved.