A recent study in the Journal of American Medical Association Pediatrics found conclusively that for teenagers between the ages of 14-18, a combination of weight training plus cardiovascular work is the best way to “fight teen obesity”. This is the headlines that went up all over the country and internet saying that the amazing findings of this study were that if teenagers did strength training and cardio work combined instead of just one or the other, they would lose more weight.
This is news?
I hate to say it but that was my first reaction. However, when I took a closer look at this study I found that there were in my opinion some flaws in the methods used to determine this conclusion.
Basically this study, which you can read HERE took 304 overweight teens and put them into four groups, one of each doing only strength training OR cardio, one doing nothing, and one doing a combination. They did this program for 22 weeks (almost six months!). They were also given diet counselling. At the end, the group that did the combination of both was found to have lost less body fat overall (compared to the strength training group), but their waist size decreased the most – by a whole centimeter. That’s not even one whole pant size.
Therefore this shows that a combination of aerobic exercise and strength training is better than strength training alone or cardio alone. Again, this isn’t news to anyone (I sincerely hope). This has been proven time and again to be the best approach for those of you out there who are looking to drop inches and pounds.
But when we look a little closer, the criteria for what they consider “overweight” has some flaws. They cited overweight as at or above 95th percentile of BMI or 85th if there was one or more risk factors or health condition already existing (like diabetes). So this means that a teenager with a BMI of above 28.5 (the cutoff for 95th highest BMI percentile according to statisticians) is overweight or obese.
Do you know what that means? An 18 year old who is 5’10” and 180 pounds qualifies for this study as an “overweight teen”. A BMI of 24 actually falls into the 85th percentile of qualification. So if my daughter is 5’3” and weighs 135 pounds according to this study she is overweight. Oh, and another note – when she turns 18, even if she is the same height and weight suddenly she has dropped to the 74th percentile. Does that make sense?
Pretty much any athletic teen is going to weigh at last that much and sometimes more. Using BMI as a method of overweight is a highly flawed criteria in my opinion. There’s a lot of other flaws. They obviously weren’t all following the same diet. Who knows how many workouts they actually completed on their own. It didn’t indicate if any of them were athletes previously, inactive or high level performers. It wouldn’t be much of a stretch for a 16 year old football player to be 5’8 and 160 pounds but have very low body fat and high muscle mass.
So this made national (actually international) news because we heard about it up here in Canada. I guess it was a slow news cycles, what with war in the Middle East and a deadly epidemic spreading around the world.
The simple fact is that kids today don’t get enough exercise. Currently 59% of adults in Canada are overweight or obese in Canada (as of 2012). We can blame a lot of things here. Increased screen time, lack of physical education and after school sports programs, deteriorating nutrition both at home and at school and simply the fact that overweight parents tend to have overweight children because kids learn many things from their parents, not the least of which is eating habits. The medical industry unfortunately can’t or won’t help because many doctors have no clue about proper diet and exercise habits themselves. Many doctors I have worked with or attended have been relatively clueless about these things because it really isn’t their job to know about it even though they are expected to.
However, if you do have a young teenager or someone younger at home then the good news is you can keep their weight down. Guess what’s a great way to get both cardio and resistance exercise without a gym?
Whether your kid is an individual sport kid (like I was – I ran track, did cross country skiing and played all racquet sports) or a team sport kid (like my sister who played basketball and hockey) there are a couple of dozen options available for each type. And even if the cost is prohibitive to a budget for things like hockey, there are tons of community resources available in any city for parents who want affordable exercise for their kids. Even something like martial arts isn’t ridiculously expensive, teaches really great fundamentals of coordination, discipline and uses lots of strength at the same time. Finding time as a busy parent can be hard, but what’s the priority – a healthy, happy kid or a promotion at work?
The sad thing is that I have trained kids as young as 8 and 10, and they could barely balance enough to walk slowly on a treadmill. Kids just simply don’t learn these things when they are developing any more. I could go on a rant about parenting and education these days but I’ll save that for another time.
So if you have a teen that is struggling with weight, maybe a good option is to get them to put down the Ipad, register them for a few sports or activities to see what they enjoy doing and get them being active and moving around more. Long term they will be much better off for so many reasons. Maybe even do it with them if you need help as well. Things like martial arts or even group exercise are easy to do with your teenager. Take your kid for a run or a bike ride on the weekends instead of staying inside. Take the whole family out for a long hike without any technology.
Like I said at the beginning, it isn’t news that kids need more exercise, or that a combination of things is likely to help them lose that extra centimeter. But it starts with actually getting them involved with exercise.
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Often when I’m dealing with clients (or even other trainers) and start talking about things like moment arms and force angles or resistance profiles I get a blank stare. I understand that because I’m a geek and like to learn about things like this, just like I would give someone a blank stare if they started telling me about their ’68 Ford and how they replaced the carburetor. Different strokes for different folks.
So when I’m working with clients and start adjusting things often I get asked why I’m doing it. Something as simple as changing an angle during a movement can provide a totally different exercise experience not only for the person involved, but more importantly for the muscles and what you are trying to do to them. A change as insignificant as 10 degrees in the knee during a knee extension depending on the position of the person’s hips can change the amount that a muscle is getting stimulated in ways that you might not think. I’m not going to get into details, but if you want to take a look at THIS study go ahead as an example of what I’m talking about. If you’re really keen I can direct you to about a few dozen more covering similar topics. Another example when dealing with shoulders is that at a certain angle of shoulder abduction (like a lateral raise) the deltoid isn’t working as the primary mover, and then all of a sudden it is.
For our purposes we can call an angle as the measure of a rotation (or an amount of rotation) around a fixed surface – that being your knee, elbow, or finger joint. In the strength work we take this to mean what angle one joint is achieving most often. For example, “going to parallel” generally means that the angle of the thigh relative to the floor is parallel, but some people also take this as achieving 90 degrees in the knee joint.
So here’s the major question that most people are asking right now – why the heck does this matter in my exercise program?
I have clients ask me all of the time how they can change up their workouts, and this is one of the simplest ways to change a fundamental movement pattern and make it do something just a little bit different to the joints in question. In RTS we call this “rotating the tires”. For example, doing a flat bench press, or a 45 degree incline press stimulate the shoulder joint (and a few others) in different ways. A pull down from straight above is different than a pull from in front of you. All of the muscles that cross the joints are still moving and being stressed – just in different ways.
Angle also can contribute a lot into how much force is required to move an object. Example – bicep curl. When a curl is at 90 degrees the force in question on the bicep muscle is potentially twice as much as it is when the elbow is at 30 degrees (towards the end of the movement). This also has to do with how far the weight is away from the joint in question like I discussed in my previous article about distance. Suddenly a ten pound weight is now a twenty pound weight and can start to cause a problem for the person moving it or put more force into their joint than it can handle, causing tendon and ligament damage.
With something as complex as a back loaded squat, there are many angles in question. The ankle, knee and hip joint all have to move together along with achieving a certain angle in the back, the feet and legs in order to provide not only safety but the ability to provide force along a chain that makes sure the muscles are being used to their maximum capacity. The ability to maintain an even hip and knee angle is essential for deep squatting, and then if the whole chain is limited by the ankle joint it will throw everything off and you won’t be able to go as deep, therefore not providing as much stimulation or even tracking into injury. There is a reason that people who have heavy loads on their back often do quarter range squats – because they simply can’t create the force to move the weight if they are at a certain angle. Here’s an illustration:
Simple things like achieving a larger range of motion during a movement can actually alter your exercise in a very significant way. One of the reasons that I’m all over my clients during workouts is because there is simple intention behind every exercise, and if it is performed differently, or with sloppy form then we can’t accomplish the goal for that particular exercise in the way it has been designed. This simple squat illustration can also show us where a person might be restricted due to something else and allow us to alter the current workout to help, not hinder progress. Imagine in each diagram what the different forces might be on the ankle, knee, hip and spinal joints.
A person’s physical structure can also have a lot to do with this. A person with longer levers like a basketball player would have a totally different movement path than someone a foot shorter and much wider like a powerlifter. If my femur is longer then the whole movement changes again and I may not be able to achieve the perfect angle. There is nothing wrong with that, but it does need to be considered when designing an exercise program. Would an exercise like a squat be as “good” for someone who can’t achieve the depth they need to get to in order to stimulate what you are trying to stimulate? Or would something else maybe be safer and more effective?
So here’s an idea – during your next workout, change a couple of angles of movement (while reducing load in order to be safe) and see if it doesn’t stimulate your body in an entirely different way. I can almost guarantee that your body will thank you for the rotation of the tires you are giving it, and your experience will be much more fulfilling. Feel free to report back to me and let me know how it went.
This series is designed to let people know about simple ways that physics affects their workout world and some simple concepts they can use to modify workouts or possibly even make them more effective and safer at the same time. Yes, I admit I am in full nerd mode here but this is just how I get through the day.
As trainers we talk a lot about tempo – or at least some of us do. Some trainers think a tempo is an old type of car. It is defined as “the rate or speed of motion or activity”. To break this down further, it means velocity, and since in the fitness world velocity has a distance vector with something attached to it we can talk about acceleration.
Fundamentally this affects the amount of force your body provides onto a movement or therefore into a joint or series of joints.
What I want you to think about is the concept that the faster you want to do something, the more force is needed to move it taking into consideration the mass in question. At that point, the actual weight involved can be part of the movement, but does not have to represent the entire situation. For example, if you are bench pressing lying on your back and you lower the bar twice as fast with downward acceleration, the force required to reverse that acceleration and push the bar back in the other direction is possibly twice as much.
One of the fundamental theories in physics is that Force = Mass * Acceleration. Acceleration is simply the change in velocity over the change in time. This means, if I lift something at a rate of 1 meter per second, and take 1 second to do it, then the total acceleration is 1 meter per second per second, or in physics notation 1m/s2. Say my mass is 100 pounds, then my total force is equal to 100. However, how does this change suddenly if I decided to lift it faster? Well, all of a sudden things change.
If I take the same weight and lift it at a rate of 2 meters/second over the same amount of time (1 second), then my acceleration is now 2m/s2. What this means fundamentally is that I have potentially doubled the amount of force required for the joints performing the movement by performing the exact same movement faster. So imagine if you will the impact on your body if you suddenly took the same amount of weight you were used to – and then doubled it. Your joints might not be able to handle the strain and torque you were putting them under and your risk of injury would increase drastically.
The factors involved here are distance travelled, the amount of mass involved (in our world we’ll take this as the amount of resistance) and also the velocity at which it is lifted. A practical example can also be for that poor guy with the really long arms who wants to be a powerlifter. He is certainly at a major disadvantage. Why? Because if he lifts a bench press bar up to his full arm extension he may have to move it many inches more than a really big guy who has relatively short arms. In fact, the distance travelled may be as much as 50% greater. This is part of the reason that powerlifters arch their backs so much, along with the fact that pushing from a decline position makes it easier to lift the weight.
Never mind the factors of muscle surface area and torque created around his major joints, he is all of sudden, if you take velocity and time into account he has to generate more force in order to move the same weight. Also, there are other things to consider like his grip on the bar and the distance it travels from his shoulder. However, if we do some quick math you will find that there are some astonishing things going on. There is a reason why most successful power lifters are big thick people with really solid technique.
For our situation, I’m going to take a guy lifting a bar .30 meters from chest to full extension, and another guy lifting something .20 meters due to arm length. They take the same amount of time to complete the lift (1 second). The mass involved is 100 of whatever unit you prefer. The first person has to generate a force of 30 in order to lift the weight. The second person only has to generate a force of 20 – or one third LESS force (according to physics) in order to move the same weight over the same amount of time, purely due to distance travelled. So the next time you see the guy with long arms pushing far less weight on a bench press, don’t be so quick to judge – he may actually be pushing far more weight in force terms than the big bulky guy beside him.
So an easy way to apply this in the gym while mixing it up is to simply try to accelerate the same weight you have previously been using – but faster. If you normally take two seconds to lift an object, try to do it in half of the time. Your joints will take on more force even though you haven’t actually changed the mass in question. It is a very simple way to change things, but can really be effective.
Please feel free to like, comment and critique this post and let me know what else you would like to hear about. Until then, rethink exercise!
At a meeting today I had a colleague ask me a simple request that I get fairly often. She wanted to have her current program she received from another trainer “tweaked” a bit because she was getting bored (that’s why they call it a “routine”). It was also a great reminder to me of the fact that some people receive guidance from a trainer and are given limited options for what exercises they can do for themselves and how that should be applied. The nice thing about the human body is that it is so versatile and can achieve so many different positions. Just for an example, with only one degree of deviation your glenohumeral (shoulder) joint can actually achieve over 60,000 different position starts. There are literally thousands of different ways you can perform exercises, but to simplify I’m going to give you some of the easier ways to change up your exercise program and give your joints a different application if you feel you are becoming stagnant.
The only thing I’m going to mention is as always that your exercise modifications should be appropriate for you specifically. This means that if your joint doesn’t want to go there, don’t force it to try. You also have to consider your ability to control the joint in question – this means, if you can’t control the movement then you should probably modify it another way. People can run into lots of trouble by trying to do things they have no business doing (and this is where people like me come in). CrossFit, P90X and Insanity are prime examples of this type of thing and is why many people tend to get hurt rather quickly. That’s not a knock against any specific methodology, it is a knock against people being told to do things way too hard that they can’t control properly simply for the sake of feeling something or hitting an arbitrary number of reps or time.
Digression over – here’s some simple ways to throw some variety into your current program and stimulate your body in a different way:
This is the most obvious one of course. Simply by once in a while increasing (or even decreasing) your weight and then doing the same movement for a different number of repetitions changes the stimulation. Next time you want to do a chest press, simply increase the weight by 10-20% and see how many repetitions you can do with good control. And for those of you who might be worried, you aren’t going to blow up into the Hulk simply because something is five or ten pounds heavier. This will also be a reminder that you’re probably not lifting heavy enough weight in the first place because if it feels easy, then it probably isn’t doing much.
If you automatically default to 3 sets of 10 repetitions, adjust and add a 4th set. Or, if this seems like too much you can always drop down to 8 reps and still add on the fourth set. Different people are stimulated differently. Some of us can even get away with one maximal set and still see excellent results. While I wouldn’t advise this for everyone, it is just an indicator that the typical way of doing things isn’t always the most effective for the individual involved. Another way to do this might be to drop a set, but take the repetitions up – so instead of 3 sets of 10, try 2 sets of 15 (if you can control the weight).
Most people lift heavy things way too fast and without any control. When I’m with my clients I am typically all over them making sure everything is perfect with every repetition and cuing as we go. To try this out, simply slow everything down that you’re performing to about half speed. You can even count out seconds if you like. This can basically take your time under tension to double or triple what it previously was, which fatigues everything that much more. Conversely, you can also adjust in mid rep – for example lowering the weight slowly and then raising it with some speed. Just be careful: speed generates inertia and momentum and can cause a massive increase in torque around your joint. The rules about control still apply.
We all normally take rest periods in between sets, but there are many people who are guilty of taking far too long or not long enough. The general rule is that the lower your repetition range is, the longer your rest period should be. Powerlifters when they are attempting triples will often rest for five minutes or more between sets. Have you ever timed your rest periods? Keeping consistent time between sets can change your workout entirely. The next time you do your workout, try to decrease your rest periods by even 15 seconds. It can mean that you lose control faster during an actual set but can also give your body a different type of stimulation. Rest periods are one thing that many people don’t even think about when they exercise
Like I explained with your shoulder, there are so many different ways that you can move through a range of motion that you really don’t need to ever do the same movement twice. In RTS, we call this “rotating your tires” because by simply abducting your shoulder to a different angle you can change how the muscles are stimulated crossing it. For example, if you normally do forward lunges, try reverse lunges or lateral lunges. If you normally do chest press flat, try incline or decline. This also means that you may have to adjust the load in question in order to perform the movement properly. It still stimulates the joints in question, just in a slightly different way in terms of force which is why you need to be careful.
Of course, you can also apply more than one of these at a time. For example, for your next workout you could do the same routine but increase your load, slow down your lowering portion and only rest for 30 seconds in between sets. Your body will have a slightly different stimulation and it will give you a bit of variety in your workouts in a very simple way. Give it a try and you can thank me the next day (or not)!