Workout trends come and go, and one of these that is getting a lot of attention is High Intensity Training (HIT). The attention, such as that in television shows like Catalyst and Michael Mosely’s ‘The truth about exercise’ (claiming that 6 minutes of exercise per week is all that we need) is largely well deserved, but as with anything, there are always two sides to the story. Let’s start with some definitions and then make sure we end up with a balanced and informed perspective!
HIT (High Intensity Training)
High Intensity Training (HIT) is the umbrella term given to a number of different high intensity training modalities. The measures used to determine the level of intensity are typically Heart Rate, or a Rating of Perceived Exertion (RPE). To qualify as high intensity, Heart Rate needs to be be over 70% of maximum heart rate (if you don’t know what yours is from personally testing it, it can be calculated by substracting your age (in yrs) from 220); and the exercise needs to be considered to be ‘hard’, or around 5-6 on an RPE scale, where 1 is “very, very easy”, and 10 is “maximal”.
HIIT (High Intensity Interval Training)
HIIT involves alternating short periods (Intervals) of work and rest over the duration of a session. The intervals can be programmed in different ways, with their length and actual intensities varying to meet the desired demands. For example, the lengths and intensities of the ‘work’ intervals can range very widely, to address either the anaerobic threshold, or maximal anaerobic power. Similarly, the rest period can be performed as active or passive rest.
HIRT (High Intensity Resistance Training)
A close member of the family, HIRT is based on the well researched varieties of cardiovascular based HIT training, but is performed largely with ‘weights’. So the work intervals may be made up of exercises that you may be more used to seeing in a gym floor, such as squats, lunges, presses, kettlebell swings, etc.
So, why would we bother with these types of training, and how do they compare to more traditional training methods?
Studies consistently show that HIIT improves metabolic health markers and fitness measures. For example Irving et al. (2008, Med Sci Sport Exerc) found that after 16 weeks of exercise, women with Metabolic Syndrome lost twice the amount of weight and fat mass, and four times the amount of fat around the abdomen when compared to those who did the same amount (isocaloric) of low intensity training. These type of studies strongly show that when it comes to energy in, or out, the amount of calories (or kilojoules) themselves are less important than the hormonal response that is created; with suggested mechanisms to explain this difference including improved insulin sensitivity and cortisol levels. More on the hormonal effect on energy in and out on weight management on a blog coming out soon!
High intensity training has been shown to reduce the risk of dying prematurely by up to 17% compared to those who do no HIT (Tanasescu et al, 2002, J Am Med Assoc), and after only one training session a week! Other often cited benefits include: reduce subcutaneous fat; improved insulin sensitivity; total body mass; aerobic fitness; blood pressure and glucose regulation; improved lipid profiles; and greater tolerance to stress! phew, great list!!
In addition, different varieties of HIT may be seen as more attractive exercise options, due to the opportunity to gain greater health benefits in less time. For those who lack motivation it may be a more enticing option than the prospect of continuously exercising for an extended period of time.
Bartlett (et al. 2011) found that the ratings of perceived enjoyment (yes, “enjoyment”) after HIIT were higher when compared to moderate intensity training. Considering that ‘lack of time’ remains the most commonly cited barrier to regular exercise participation, this seems too good to be real, right?! Well, perhaps.
There’s certainly some things that we need to be aware of:
While the physiological effects are evident, the duration of most studies is very short, with very short follow-ups, and largely in unhealthy populations. The long-term effect of has not been well established and if I was to take a guess I would say that eventually there would be a decreased return on investment. A yet to be published (large scale) study looking at physical activity trends in Australia shows that more Australians are performing vigorous physical activity; but less low-moderate physical activity; and the amount of sedentary time continues to increase. It appears that while HIIT is certainly more time efficient, the less time we spend moving the more opportunity we allow for sedentary time. This might help explain the increasing rates of Type II diabetes and Cardiovascular Disease, as it is well accepted that the negative physiological effects of sedentary time can cancel out and even outweigh the physiological benefits of exercise.
In addition, by its very nature, high intensity exercise carries a greater risk of injury, particularly for those new to exercise, so careful and guided progressions are recommended!
To conclude, other than the imbalance that is created between active and sedentary time, by shortening exercise time, I believe there is another significant issue with the way that research on HIT training is communicated to the public. The type of reporting seen in the media only reinforces the mindset that exercise is like some nasty medicine that we need to take, so we are best off pinching our nose and getting it over and done with as fast as possible! Surely the message should rather be one of promoting an active lifestyle, and that HIIT training can be a fantastic adjunct to that? Our body is the machinery that we have to go out and experience the world in and with, and the broader and deeper our physical capabilities, the wider the range of experiences we can potentially have. While High Intensity Training can certainly help us improve some specific health measures, does it help us live our lives more fully?
Written By Max Martin
Transitioning from military service to civilian life can hold many challenges for veterans and health matters can be at the forefront. Life in military service typically involves free medical, dental and health support with many systems in place including compulsory annual check-ups. This allows our service members to get on with doing their jobs without having to worry about when their next check-up is due; it is all organised for them, minimal planning necessary.
Difficulties can begin when veterans discharge from service. It is very common for them to let their medical and health support fall by the wayside. They no longer have a system reminding them of when they are due for a check-up and on top of this, the services provided are no longer free. They also need to find themselves a network of medical and health practitioners, where previously these decisions would have been based purely on who was available at the base medical facility.
With this in mind, it is critical that veterans establish a consistent and reliable network of practitioners for their medical and health support. As part of this process, it is highly recommended that they schedule regular check-ups and reviews in advance. This will provide some semblance of familiarity for them, and will make it harder for veterans to become complacent about their health.
Military service also typically involves daily Physical Training (called ‘PT’) as part of the employment requirements. Usually PT would be conducted within units with military members training alongside their colleagues. Again, this format removes any responsibility from the members for the organisation of their own fitness training and the group dynamic aids in fostering military esprit de corps. Post-transition, they no longer have daily fitness training organised for them, and in many cases they may not have friends or colleagues involved in organised fitness training that they can participate in. Whilst organised group PT doesn’t have to be a part of a veteran’s life after service, it is still important that each veteran finds a form of physical activity to participate in. This could take the form of Personal Training, Group Fitness classes, organised sports or outdoor PT groups.
The issues we have discussed not only have a direct impact on a veteran’s physical health, but they can have lasting effects on mental health. In this era of high operational tempos for the Australian Defence Force, it’s not uncommon for veterans to complete a number of operational deployments to the world’s danger zones during their period of service. We have seen through a growing number of media reports and government statements that this is having a huge impact on the mental health of our veterans. These mental health issues are one of the major problems affecting our veteran community, and they must be part of any discussion regarding veterans’ health.
Another issue facing our veterans as they leave their service lives behind them is the loss of camaraderie that they experienced while in uniform. Upon discharge many veterans move back to their hometowns, or perhaps to a new city where a new job awaits them, effectively creating distance between themselves and the colleagues they had a unique bond with. This scenario leaves many of our veterans feeling as though they don’t belong or fit in with their new surroundings. Signing up to a local sports club, or an organised fitness program can assist with this transition by providing some sense of camaraderie and being part of a team, whilst keeping veterans physically active.
Whilst it’s not the goal of this blog to discuss mental health issues specifically, exercise has been clinically shown to provide positive benefits to mental health and we strongly urge all veterans to participate in a regular exercise program not just for the physical benefits, but the mental benefits as well.
In summary, it is highly recommended that all veterans follow this short list of very simple guidelines in order to maintain their health:
- Establish a reliable network of medical and health practitioners
- Schedule appointments, reviews and check-ups in advance
- Participate in regular physical activity
- Enjoy organised sport or some form of group activity
- Make mental health a priority
We have all heard about that uncle that didn’t smoke or drink, and went to bed early, and died of a heart attack while going for his morning run, right??!! Why would we even bother?!!
Well, there’s some truth to that fear, as your risk of injury and other negative health events certainly increases somewhat WHILE you are exercising. Think about it, your car is much more likely to rattle, overheat, or have a tire blow out while driving at high speeds, than while it’s parked in your garage, right?! A wise colleague of mine once said at a presentation on the matter:
I have never seen anyone get injured while standing at the front of a shop while window-shopping!
and I have to agree, neither have I. And the more extreme the exercise, the greater the chance of a negative outcome. Take Mountaineering for example, which is 50-100 x more risky than your regular structured exercise, with a 1 in 400 chance of dying in any given year!!
BUT, here is the catch: Doing nothing is 20x more risky than moutaineering!!
It is very clear that being sedentary and sitting for prolonged periods of time is extremely dangerous for us. So much so, that when compared to the rightly criticised smoking, which takes 11mins off your life expectancy per cigarette that you smoke; one hour of sitting watching TV takes 22 mins off your life!
Sitting for 10 hours a day is equivalent to being like an average smoker (20 a day). Both of which lose 1.5 years for every 10 years of the habit.
So how do we reverse this increasing level of risk? The clear answer is to obviously move more! Make sure that you aren’t sitting for an hour without having gotten up. In addition good health (FESS) behaviours reduce the risk of premature death by 65-84%
One other thing to watch is stress. Those that report being “Much more stressed than usual” are at a similar level of risk as those that smoke 20 cigarettes a day!! So, how can you combat this? We know that hobby activities reduce risk by 27%; that relaxation exercises reduce risk by 23%; and that simply ‘enjoying’ life reduces the risk of cardiovascular disease by 38% in men and 11% in women
Ok, time for me to get up and do a few squats!
I hope I haven’t got any musos falsely excited based on the heading… but if I have, then you might as well just tune in (ah, see what I did there…ha…ha…ahhh….ok…I’ll get on with it…).
As we near the final development and exciting launch of our MovementScreen, I’ve been spending a lot of time talking to people about the initial ‘evaluations’ they go through when starting exercise. This is something I believe in incredibly strongly, as a very important undertaking to ensure safety and success of an exercise program. As a business owner I’m also very interested in those initial evaluation and planning stages of any project, as they are so critical to the success of the project. Interestingly however, when it comes to business projects, I get excited and jump head first into it.
If the entrepreneurial spirit were a disease, I would have been diagnosed as being in its terminal stages! The issue with this, is that often I end up walking into roadblocks and diversions, that, if I had spent more time in the planning stages exploring, I’m sure I would have been more successful, with a lot fewer bruises! I would have been a lot happier at re-evaluation stages.
A wise friend of mine once said to me as I excitedly asked when we are going to implement a project: Max, a good project devotes a third of its time to planning! Wow, the patience required for this! Needless to say, this project delivered very good outcomes for the relevant association because we went through that process.
So if this Project Planning 101 lesson is obvious to you (add I’m painstakingly learning it myself), then let me encourage you that, by looking at it from my professional perspective, this also applied to your health and exercise endeavours:
- Make sure that you plan what you want to do and achieve
- very importantly, have someone help you identify barriers to your success. these could include past injuries, movement limitations, lack of specific knowledge, etc.
- implement these things into some initial testing/evaluations, that will help you objectively measure your success!
These evaluations could include an understanding of your current body composition – rather than just what the scales tell you; or a movement score; or a measure of pain; or an objective fitness test. All of these can help you plan and guide your health journey.
Last week I saw a report on the ABC about the growing prevalence of overweight or obese kids in Australia, and it sparked a lot of angry thoughts! As one my areas of passion is seeing healthy active kids!
The stats, as you can imagine, are scary: Back in 2000, approximately 20% of teenagers were overweight or obese, now its 25% and a study conducted by the Victorian Dept of Hman Services predicts that this number will increase to 33% by 2025 (Future prevalence of overweight and obesity in Australian children and adolescents, 2005-2025 Department of Human Services, March 2008)
The consequences are sad and cruel: greater prevalence of cardiovascular disease, Type 2 Diabetes, a whole range of cancers, and mental health issues.
The reasons are both staggering, yet unsurprising:
The study reported on by the ABC was conducted by the Cancer Council and National Heart Foundation, and it revealed teens were spending too much time in front of the television with 58 per cent of students having at least three televisions in their home and 40 per cent with video games in their bedrooms. 75% of teenagers were spending more than two hours in front of screens (for school work or entertainment). A huge 82% are not engaging in more than 60 minutes of physical activity per day.
So what are we going to do about this sad state of affairs? All this takes me back to a paper I was privileged enough to co-author a few years ago. It showed that not only are both adults and children under active, but that the association between parents and their kids’ physical activity is decreasing. So the behaviour modelling strength of parents’ activity is influencing kids less! While the reason why is unclear; my guess is that its due to our changing behaviour patterns. We just don’t see as many families going for walks or bike rides together. You don’t see as many dads kicking the footy with their kids. Now we go to the gym or social sport on the way to or from work, and we are ‘done’ by the time we get home. So while we may be active, our kids don’t see us being active, so they don’t learn from our exercise behaviours!
So lets get out with our kids more. Even when I’m being active on my own, I try to make a point of telling my kids how much I enjoyed my run or bike ride around Adelaide’s beautiful trails!
Martin M, Dollman J, Norton K, Robertson, I. (2005) A decrease in the association between the physical activity patterns of Australian parents and their children; 1985-1997, Journal of Science and Medicine in Sport, 8(1): 71-76.