Lesson video

Hello and welcome to today's lesson.

My name's Mr. Swaithes and today, we're gonna be looking at those long-term adaptations or the long-term changes that your body makes in response to a training programme or repeated bouts of exercise.

The lessons called "Long-term Adaptations to Training" and it comes from the unit, "Anatomy and Physiology: The short and long-term effects of exercise." By the end of today's lesson, you'll be able to describe the long-term effects of exercise on your body.

We'll be looking at a number of keywords throughout the lesson, but importantly, you'll want to understand what long-term effects of exercise means, what hypertrophy is, if you don't already, what fatigue is and what capillarisation is.

So you might want to pause the video for a moment while you make a note of these definitions, but of course, we'll be revisiting them as we go through the lesson and I'll explain them in more detail there.

Today's lesson is broken up into three parts.

In the first part, we'll be looking at the effects of a period of training on the musculoskeletal system.

And the second part, we'll be looking at the effects of training on the cardiovascular system.

And then in the third part, we'll be looking at those adaptations or the the effects on the respiratory system.

So three really interconnected sections to today's lesson.

I hope you ready? Let's get going.

The body's amazing, isn't it? It's able to adapt and respond to the changing circumstances or conditions that we place it under.

And training is basically repeatedly put in your body under that strain in order for it to adapt and respond.

So when you commit to training over a period of time, your body adapts and it changes to cope with the demands that are placed on it.

Sofia is wondering, "What adaptations or long-term changes do you think happen following a period of training?" And Aisha asks, "Does different training have different effects?" What do you think? Well, if we focus in on the skeletal system, Andeep is wondering, "How does training affect that?" Well, let's take a look.

So interestingly, your bone density increases following training, particularly, if it's weight-bearing exercise.

And let's remember that if we have improved or increased bone density, that's gonna aid a performer and in fact, it's gonna aid anybody.

Why do you think that is? Well, if you were to do weight-bearing activities, so anything where you are on your feet, so this doesn't include cycling or swimming because they are not weight-bearing activities, but that puts stress on your bones and that stimulates extra calcium deposits, which will then lead to the bones becoming denser and stronger.

That's gonna help prevent it against osteoporosis, which is something that lots of people suffer with in old age.

It's a health condition of fragile bones.

That means they're more likely to break.

I'm sure you'll have heard of older people perhaps breaking their hip or breaking bones more regularly, for example, they fell down the stairs.

Whereas the younger bones have more calcium, so they're able to, I guess, cope with some of those falls without leading necessarily to a break.

So a good diet is also important if you want to prevent osteoporosis.

What about your muscular system then? If you train a number of times a week for six or more weeks, what will happen to your muscular system? Well, there's a number of changes, but importantly, and perhaps the most important one for you to remember is that there's an increase in hypertrophy or muscular hypertrophy.

So that means that your muscles get bigger and they get stronger.

And as a consequence of your muscles getting bigger and stronger, your component of fitness of muscular strength will increase as well.

So you'll be able to lift heavier weights or cope with a heavier resistance.

There'll also be an increase in your muscular endurance.

And actually, depending on what sort of training you do, you might focus on that muscular strength, almost the one repetition max, or you might focus on muscular endurance, your ability to keep lifting weight or catering against the resistance for a long period of time.

And you'll also get an increased resistance to fatigue.

So that fatiguing feeling is where, you know, you get shaky, heavy legs or the lactic acid is really built up to a point where you have to slow down or stop exercising and your body is better able to cope with both that lactic acid fatigue, but also what we call neuromuscular fatigue.

So again, if you're into your powerlifting or weightlifting, you might have come across that term neuromuscular adaptation.

So actually, a lot of the strength gains initially in a strength training programme come from better connectivity between your brain and your muscle, able to recruit more muscle fibres to lift heavier weight.

So that neuromuscular fatigue is delayed, but so too is that lactic acid accumulation which causes fatigue.

Okay, let's dig a little bit deeper then into what is muscular hypertrophy? Well, when we exercise our muscles regularly, they increase in size and in strength.

Small muscle tears or micro tears as we call them, help the muscle grow back bigger and stronger.

And if you imagine, your muscles are almost like a big packet of spaghetti, loads of long fibres running past each other.

And actually when your muscles contract, they sort of grab hold of each other and pull their way past like this, and that's your muscle contracting.

Well, each one of those fibres grows thicker and stronger as a consequence of being kind of subjected to tiny tears that then cause growth and repair.

Let's remember though that rest and recovery alongside a good diet, for example, including proteins, are also important for muscular growth and repair to happen.

So it's no good just training every day and lifting heavy weights every day, you need to spread it out.

You need to have a good programme of rest in between heavy bouts of exercise.

Let's do a quick check.

Which of the following is not a long-term benefit of training on the musculoskeletal system? Is it A, increased muscle hypertrophy? Is it B, increased bone density? Is it C, increased length of bones? Or is it D, increased stroke volume? That's right.

You do not have an increased length of bone as a consequence of training.

And of course, you do have an increased stroke volume, but that is a cardiovascular system response, not a musculoskeletal system response.

So the two we need to be mindful of are muscular hypertrophy, which leads to increased strength and muscular endurance, increased bone density, reducing the risk of osteoporosis.

And then also we talked about delaying fatigue or being able to cope with exercise better, didn't we? So Sofia is wondering and asking that she likes the sound of all those benefits, but how long does she need to train for to see an effect? And Aisha says, "Well, surely it depends on how hard you train." Well, absolutely, it depends on lots of factors, actually.

So your age, your current fitness level, but you typically need to train a few times a week for six or more weeks before you start to see the long-term effects or adaptations of the body to training.

Okay, true or false? Microscopic tears in your muscles are bad and should always be avoided.

That's right, it's false, isn't it? And can you tell me why? Yeah, so microscopic tears are necessary for your muscles to grow back bigger and stronger.

We obviously need to avoid major tears in our muscles or training too hard.

We call that over training and also training too hard, too fast, so overloading the body too quickly.

We need to make that progressive, don't we? But there's a certain amount of training and aching is required the next day if you want to increase your muscle size and adapt to training.

So a certain amount of aching the next day is perfectly normal.

And let's remember that training can be tailored to suit the needs and motivations of different individuals.

So if you lift heavier weights or work against a heavier resistance with lower repetitions, then that'll train your muscular strength, your one repetition max, potentially.

Whereas if you were to lift lighter weights or work against a lower resistance with higher repetitions, then that'll train your muscular endurance and you'll need to modify which of those you decide to do based on your training goals.

What sort of strength would you prioritise developing and why? Okay, that brings us nicely into this first task for today's lesson.

So I'd like you to complete the following table to summarise the musculoskeletal adaptations to training.

You can see I've done a few sections for you.

In the first column we have adaptations, then we have an explanation, and then in the final column, that's where you would put the benefit to the performer.

So pause the video now whilst you have a go at that and then come back to me when you're ready.

Well done, let's see if what you put was similar to, here's one that I made earlier.

So the adaptation of increased bone density, I'm hoping you put something on the along the lines of that that causes a denser and stronger bones.

And a benefit of that is you're less likely to break or fracture your bones.

The second one, it was already saying that this is an increased muscle size and I'm hoping that you manage to remember that the adaptation is called hypertrophy or muscular hypertrophy.

And the benefit of that is it can contract your muscles with more force.

Then we have the two further adaptations, which are increased muscular strength and increased muscular endurance.

If you increase your muscular strength, you'll have a bigger one repetition max, and therefore you can contract with bigger force.

Whereas if you have an increased muscular endurance, you can contract for longer periods of time before fatigue sets in.

So you can contract repeatedly for longer.

I hope you got all of those.

Okay, let's move into the second part of today's lesson where we focus in on the cardiovascular system.

So and Andeep is wondering, "What about the cardiovascular system? What long-term effects or adaptations does training have on it?" And Sam says, "Well, that includes your heart, your blood and your blood vessels." So let's focus our attention there.

What do you think happens to the heart, the blood and the blood vessels if you followed a training programme for a period of, let's say six weeks? Okay, so let's look at some of those training effects on the cardiovascular system.

So there will be an increase in cardiac hypertrophy.

So your heart grows bigger and stronger.

As a consequence of that, your resting stroke volume will increase, your maximum stroke volume will increase.

So the maximum amount of blood you can pump out of your heart per beat.

Your maximum cardiac output will increase.

So the maximum amount of blood you can circulate around your body per minute will increase.

And also you have an increase in capillarisation.

So you grow the number of capillaries that you have surrounding the alveoli, but also surrounding the muscle cell.

And as a consequence of that, gaseous exchange can happen much faster, and then you also have faster recovery from exercise.

So you're able to train hard, get exhausted, and then perhaps quickly recover to be able to train or compete again soon after.

The biggest one to remember though is what decreases as a consequence of training and that's your resting heart rate.

So lots of us use this resting heart rate as a good gauge for how fit we are or at least how aerobically fit we are.

Let's do a quick check before we drill into a bit of more detail on each of those.

So which of the following is not a cardiovascular system benefit of six or more weeks of training? Is it A, reduced heart rate? Is it B, increased maximum heart rate? Is it C, increased maximal cardiac output? Or is it D, increased stroke volume? Which of those is not a benefit of training? That's right, isn't it? It's increased maximum heart rate because we know that heart rate is related to your age.

So your maximum heart rate as a rule of thumb is 220 beats per minute minus your age.

So actually, the older you get, the lower your maximal heart rate becomes, whereas the others are all true.

Okay, and why does that happen? Well, training puts strain on your heart and this causes it to get bigger, to get stronger and to get more efficient.

And what did we call it when your muscle, because of course, the heart is a muscle, isn't it? It's a specialist type of muscle called cardiac muscle.

But what do we call it when muscle gets bigger and stronger? That's right, it's hypertrophy, isn't it? So the heart can contract with more force and hence, eject more blood per beat because it's got bigger and stronger.

And this results in an increased stroke volume, the amount of blood ejected from the heart per beat.

And because of that cardiac hypertrophy and that increase in stroke volume, your resting heart rate can decrease while still maintaining that same cardiac output.

So the same amount of blood circulates around my body per minute if I'm well-trained or if I'm not well-trained.

But if I'm well-trained because the stroke volume is bigger, my heart rate can be lower.

So, because our stroke volume is increased and your maximal heart rate is only affected by your age, your maximal cardiac output will also increase.

So the amount of blood you can pump around your body per minute increases.

And we're also able to recover faster after exercise.

So I don't know whether perhaps you've had a period in your life where you've not been very well-trained and you do about of exercise and it takes you a really long time to recover afterwards, before you could even consider doing that bout of exercise again.

Whereas if you're well-trained, given a short amount of time, you're ready to get up and go again.

So endurance exercise is best for cardiac hypertrophy.

So long distance running, cycling, swimming, jogging, or even playing sport where you're working for a long period of time, you keep moving.

But also interestingly, weight training stimulates cardiac hypertrophy as well.

So if you're not someone that likes to pan the streets and get lots of miles under your belt, you can go to the gym and that also will have positive effects on your heart muscle.

In fact, any training that gets you outta breath will do it, but it's got to get you beyond that point that your body is used to.

So if every day you walk to school, whilst that might get you a little bit outta breath, your body soon adapts and that becomes its new normal.

So you might have to walk faster to school or into space a bit of jogging with your walking to school in order to get out of breath, in order to get that cardiac hypertrophy and the benefit from it.

Okay, let's drill into what we mean by capillarisation then.

So the capillaries are what surrounds your alveoli in your lungs.

And we can see an image of this here with a really good blood supply around the alveoli, we're able to maximise gaseous exchange.

So training causes an increase in those capillaries or capillarisation as we call it.

And that means that you grow more capillaries to surround the alveoli at the lungs.

And as a consequence of that, more gaseous exchange is possible.

So more diffusion of oxygen and carbon dioxide.

So if you've got an increased capillary network, you're able to deliver more oxygen to the working muscles and remove more carbon dioxide and that further improves your aerobic respiration or your aerobic endurance, or your cardiovascular endurance.

So you're able to do long distance events better.

Let's do a quick check.

True or false? Unfit individuals have a lower heart rate.

What do you think? That's right, that's false, isn't it? And can you tell me why? Well done, so unfit individuals have a higher resting and exercising heart rate for any given intensity compared to an endurance-trained individual.

So for example, if we had someone who was endurance trained on a treadmill next to someone that was not trained, someone that was unfit and they were running at the same speed, the unfit individual would have a much higher heart rate than that trained individual.

And that's because the trained individual has had cardiac hypertrophy, which enables more blood to be ejected per beat.

We know that's called stroke volume, don't we? And therefore, they can reduce their heart rate and whilst still maintaining that same cardiac output.

So we've got a picture here of Emma Raducanu, and as we know, she's a really keen tennis player, isn't she? And this second task for today's lesson, I'd like you to explain at least three long-term adaptations that occur in her cardiovascular system as a consequence of a rigorous training programme that includes some endurance and some strength training elements.

Pause the video now whilst you do that, dig into the detail of three long-term adaptations and come back to me when you're ready.

Okay, let's have a little look and compare.

Perhaps this is along the lines of what you came up with.

So firstly, the heart wall becomes bigger and stronger.

This is called hypertrophy.

So cardiac hypertrophy is the buzzword that you absolutely need to have in part of your answer.

And it means that more blood can be ejected from the heart in each beat.

And we call that stroke volume, don't we? As a consequence of that cardiac hypertrophy, your heart is more efficient and therefore, your resting heart rate decreases.

So a key word there is efficiency, but another key word is that idea of a reduced or decreased resting heart rate.

I'm hoping you got that one.

And then thirdly, capillarisation happens.

So that means you've got a denser capillary network which speeds up gaseous exchange at the alveoli in the lungs, but also at the muscle cell.

So the key words we really want there are around hypertrophy, decreased resting heart rate and capillarisation.

Well done, if you've got all three of those.

Okay, that takes us through to the third part of today's lesson where we're gonna look at the respiratory system.

So Izzy now is wondering, "What about this respiratory system then? What long-term effects does training have on it?" And Jacob's here to remind us, "The respiratory system is the system that helps us breathe in and out," doesn't it? So what do you think will change at your respiratory system if you've done a period of perhaps six or more weeks of training? Okay, let's take a look at them then.

So the training effects on the respiratory system include: Increased strength of your respiratory muscles.

So your diaphragm and your intercostal muscles, which are the ones in between your ribs, increase in strength.

Increase tidal volume during exercise.

Increase maximal minute ventilation during exercise.

Increased aerobic capacity.

And therefore, faster recovery time from exercise.

Let's drill into those into a little bit more detail.

So any exercise that gets us outta breath will put strain on the respiratory system, in the same way that it's putting strain on your cardiovascular system and also on your muscular system.

Long distance endurance events have the biggest effect there.

So if done regularly, this will cause long-term adaptations or changes to help us cope better with an increased demand for oxygen.

Like any muscle, the diaphragm and the intercostal muscles hypertrophy.

So there's that word again.

Our muscles hypertrophy like skeletal muscles, so your biceps, triceps, quadriceps, hamstrings will increase and hypertrophy, which helps your musculoskeletal system.

Your cardiac muscle with hypertrophy, so that helps your cardiovascular system.

And now we've got our diaphragm, that sheet of muscle underneath your lungs and your intercostal muscles, the ones in between your ribs, also hypertrophy.

And here we've got an illustration that reminds us that if the respiratory muscles are bigger and stronger then we can: Increase the volume of the thoracic or chest cavity further when we breathe in.

So, (deeply inhales) we can get a bigger volume of air into our lungs.

We can increase our exercising tidal volume, so the amount of air flowing in and out of our lungs per breath increases.

And we can increase the minute ventilation.

So minute ventilation is the amount of air that we're exchanging, the amount of air we're inspiring or expiring per minute.

And if we're getting more air into our lungs per minute, then that means more gaseous exchange will happen.

And as a consequence of that, we've got increased aerobic capacity.

So we're able to fend off that lactic acid accumulation.

We're gonna keep working aerobically rather than working anaerobically.

Let's do a quick check.

Which of the following is a respiratory system benefit of endurance training? Is it A, increased stroke volume? Is it B, decreased resting heart rate? Is it C, increased strength of diaphragm in intercostals? Or is it D, increased bone strength? That's right, it's increased strength of diaphragm in intercostals, isn't it? So the other three answers are true.

We've gotta be really careful reading the question because this question is asking just about the respiratory system and answer A is to do with the cardiovascular system.

So is answer B and answer D is to do with the skeletal or musculoskeletal system.

So these factors improve performance due to: Increased gaseous exchange.

Increased aerobic capacity.

Delayed crossing of that anaerobic threshold.

So you won't build up lactic acid quite as quickly, but also, you can cope better with lactic acid in your body.

You can also resist fatigue better.

And you can also recover faster after exercise.

And that might be when your race is finished and therefore, you can race again soon.

Or it might be that perhaps, you know, let's think of a rugby player, they get a halftime little bit of rest and if they're fitter and stronger, they'll be able to recover faster during that halftime to be able to go hard and fast again in the second half.

So as a consequence of all of these changes, they're likely to improve your performance.

But let's remember that performance is more than just those physiological factors.

So performance also requires, depending on what it is that you are doing, the mental strength, but also the tactical awareness and thinking in the moment.

So, true or false? Maximal minute ventilation decreases following endurance training.

What do you think? That's right, it's false, isn't it? And can you tell me why? Yeah, so training results in an increased lung capacity and stronger respiratory muscles.

And as a consequence of that, our maximal minute ventilation increases following training.

Well done with that one.

Which brings us nicely into the third and final task of today's lesson.

So I would like you to explain the respiratory system responses to endurance training.

So that's this section of the lesson summarised by explaining the respiratory system responses to exercise.

But then I want to bring together what we've learned through the whole lesson.

So for each of the body systems in the table below, I'd like you to identify one long-term effect of regular training.

So one adaptation and how it could benefit performance in sport.

So pause the video now, whilst you have a go at that and come back to me when you are ready.

Well done.

So let's have a look at what you came up with for question one first, so this part of today's lesson about the respiratory system in particular.

So you might have said that the diaphragm and the intercostal muscles hypertrophy, which means that they can contract more forcefully.

You might have also said that this results in the ability to exchange greater volumes of air with each breath.

And we know that as the tidal volume, don't we? And that significantly increases your minute ventilation, which means more oxygen is delivered to the body and more carbon dioxide is removed from the body per minute.

And as a consequence of that, your aerobic capacity or your cardiovascular endurance will improve.

You can also recover faster from exercise.

So you can work hard, have that bit of rest, and then go and work hard again.

Which of those five did you get in your explanation? And then we take ourselves through into the second part of this question where this table summarises everything that we've learned in today's lesson.

So if we look first at the skeletal system, and actually you could combine these top two boxes to be the musculoskeletal system, but let's look just at the skeletal system.

You have an increased bone density and increased ligament and tendon strength.

And as a consequence of those, you've got a reduced risk of breaking a bone and a reduced risk of a joint injury.

So a sprain for example, or maybe an Achilles rupture.

Then if we look at the muscular system hypertrophy of those skeletal muscles like the biceps, triceps, quadriceps, hamstrings, leads to increased muscular strength or endurance depending on how you train.

Whether you're training with low resistance, but high repetition.

So you'll get greater muscular endurance or maybe you're going closer to your one repetition max and you'll get bigger muscular strength.

Then we move into the cardiovascular system.

So cardiac hypertrophy and an increase in red blood cells leads to an increased ability to exercise harder for longer.

And then finally, in the respiratory system, we can see that hypertrophy of the respiratory muscles, so your intercostal muscles in your diaphragm will increase gaseous exchange, which means more oxygen is available to enable you to exercise harder.

And all those four body systems are working together to mean that you're gonna be able to perform better in sport.

So that leaves me just enough time to summarise today's lesson, all around those long-term adaptations or long-term changes thanks to training.

So we remind ourselves that long-term effects of exercise refers to those benefits or changes in health and in fitness after a period of regular training.

And if you do that regular training or regular exercise, it leads to: Increased bone, muscle and joint strength.

Cardiac hypertrophy, and an increased oxygen carrying capacity of the blood.

So you actually grow more haemoglobin in your blood, which means you have an increased red blood cell count and can carry more oxygen in your blood.

You have a reduced resting heart rate 'cause your heart's become more efficient.

You have an increased capillary network.

So we call that capillarisation, which means better gaseous exchange will happen.

You have stronger respiratory muscles so your intercostals and your diaphragm will get stronger.

And as a consequence of that, you'll have increased lung volumes.

And also, we have improved ability to recover faster after exercise.

So you can train hard, recover fast, and go again.

And as a consequence of all of those factors combined, you'll have improved sporting performance as long as of course, you have those tactical and technical benefits as well.

So you get better at how you think through how to respond to something, but also your your technical ability in whatever sport it is that you are playing.

And then more broadly than that, you'll have improved general health.

I hope you've enjoyed today's lesson.

It was an awful lot for us to get through again, and I look forward to seeing you again next time.