The physiological changes that take place in your body during a block of training that allows you to record a higher ftp on your next test are wide reaching and varied.
I thought i would try and explain them , so that you can understand what is happening to your body and maybe make a few small lifestyle tweaks to enhance the improvement curve.
Everybody likes to be rewarded for a good block of training with a new FTP. It is not just luck when this happens, it is as a result of complex physiological and psychological developments throughout your body.
FTP increases as a result of increases in aerobic and anaerobic fitness, we think of ourselves as needing good aerobic fitness to be a good endurance cyclist, but you also need to have the ability to work anaerobically, even riding at sweetspot, or nearer FTP and definitely above FTP there is a an anaerobic component to the energy systems, so it is important to fuel and train both systems to be a successful cyclist.
Things that bring about changes in FTP.
- muscle fibres increase in size, both slow twitch and fast twitch and the combination of the 2 working together (mid twitch if you like) it’s this combo that gets stressed by sweetspot training. Depending on your genetic makeup you may have more of one type or the other, and the type of training you do helps the muscles to utilise the ones that are going to be most effective, in some cases you can for example increase the number of fast twitch fibres by sprint and explosive power training, and increase the slow twitch fibres by doing long steady endurance rides. To be a good all round cyclist you need to work on both.
- improved usage of lactate- the body does not accumulate it so fast as you get fitter and stronger, and utilises it to create power, the point at which levels accumulate to such a point as to make you back off gets extended.
- increase in muscle capillarisation- this is the process in which capillaries are formed, increased numbers raise rate at which gaseous exchange and removal of waste products takes place via the capillaries in the muscles.
- Improvements in fat utilisation as an energy source, essential for endurance athletes.
- improvements in the recruitment of fibres in the muscles that you use for pedalling and the relaxation of the antagonist muscles (the opposites to the ones you need to use) this recruitment/relaxation system allows muscles to work better.
- Pedal stroke becomes smoother and more efficient – using less energy for the same output.
- neural input from your brain goes down, this means that it takes less energy to activate the fibres to do what you need them to do – this results in the same energy output from your brain allowing your muscles/fibres/cells to work harder.
- increase in glycogen storage capacity. With training and good diet with adequate carbs you can increase your muscle glycogen storage capacity by up to 1.5x. this means that your time to failure with no additional nutrition will increase over time and fitness by up to 1.5x. (this can be further extended to up to 3x with pre event carb loading)
- you will become more efficient at oxidising carbs- so less is wasted and more glucose is used for creating ATP, the energy used at a cellular level.
- cardio-respiratory changes- VO2 max may go up to nearer your genetic ceiling. your ability to work for longer at a higher percentage of your VO2 max will also increase.
- your muscles round your lungs will get stronger allowing you take larger breaths of energy giving oxygen.
- the muscles of your heart will get stronger increasing the amount of blood that is pumped round out with each beat of your heart.
- you will experience improved oxygen extraction, ie your cells will get better at utilising the oxygen that is in the cells for energy.
- you will develop more plasma – this reduces the viscosity of the blood allowing it to flow more efficiently through the capillaries.
- you will make more blood cells so that more oxygen can be carried around your body per minute. ( haematocrit goes up) the number of blood cells per litre may not increase due to the larger circulating volume.
- due to higher levels of plasma your thermo regulation improves, allowing you to go harder for longer without over heating.
- you become better mentally at managing pain and discomfort, allowing your body to push on as your head copes with being uncomfortable.
A few thoughts on feeling fit snd strong and what it does! when you are fit you feel different. Squeeze your quads and feel the muscle beneath- a ‘fit’ muscle feels larger and denser, and as your own fitness goes up and down throughout the year you will notice a difference in how your leg muscles feel.
When you are fitter you have a level of confidence in your body that is less present when you are less fit- enjoy that feeling, it is always earned, and never given easily.
You can run for a train and you don’t die, you recover from stress and stressful situations, having fitness makes you more resilient in all aspects of your life. Some of this will never go, even as your fitness may wane over time.
Look at the pedal stroke of an untrained cyclist and compare it to a pro- like Geraint for example – his stroke is smooth and efficient- he goes just a little bit further with each turn of the pedals than you or I, his cruising is similar to our ftp efforts, his ftp will be a fantasy of around 6w/kg….! This is the result of hours of training effect on all the physiological and psychological points listed above. Its food for thought!
So as you do your next FTP test- marvel at all the changes that have taken place in your body, and when you get a higher result, know that everything has been in place, all the ducks have lined up and those changes have taken place. Some aspects may be greater for each individual than others in any given training period, always always leaving room for more improvement at another time.
If you don’t get the changes that you desire, reflect on your recent block of training
- Are you adequately rested and recovered- not so much that your ftp can actually go down a little, but enough that you are fresh enough to perform to your best ability .
- -has it been consistent, have increased your training stress a little bit each week. Is your head in the right place, do you/can you believe that you can do better.
- Have you been very stressed at work or in your home life, both these things can affect your ability to perform.
- How is your sleep- are you getting enough, could you be chronically sleep deprived ( average of 6 hours or less a night over extended periods of time).
- how has your nutrition been- did you eat enough carbohydrate prior to testing.
All these things are changeable and may need reflection before your next test- nothing is permanent and little changes will help you to get the results that you desire.