Preparing for Endurance Events: Gears and Cadence (Part 3 of 5)

Thursday, June 20, 2019

So the poor guy in the picture here is falling off because he was going up a hill which started to ramp up unexpectedly, and he was in the wrong gear.


Realising this too late, he tried to change from the big ring at the front to the small ring, but chains don’t like to move sidewards when under huge amounts of stress; because the change in ratio from your big ring to your small ring is quite a large step, in this case the chain did not engage with the small ring and was flung off. With no chain he had no control or ability to turn the pedals and so hit the deck, more of a unexpected dismount than a fall, perhaps a cut knee and bruised ego. It could have been worse, he could have snapped the chain, which would take a while to get repaired or replaced.

You can expect to get a lot of these types of hills here in the UK . I will try categorise them into two types into “short and sharp” and “long and steady”.


Short and Sharp come at you with very little notice and you need to anticipate well beforehand, shift onto the small ring as you reach the bottom of the hill (it is unlikely that you will be pedalling hard at this point), thereby avoiding the chain problem described earlier and once on the small ring, progressively and deliberately shift the gears at the back, matching your pedalling speed….and expect to need to be in your lowest gear early on (if in doubt this is the big cog at the back….if you are worried about the hills get a cassette that has a big cog with 30 or more teeth).


If you have any hills near you like this, go and practise shifting gears until it is nice and smooth. A good rule of thumb, if it goes down sharply, it will go straight back up just as sharply, think “V-shape” valleys due to millions of years of erosion from stream at the bottom, with no ice-age glaciers to soften the valleys in the south of England.
For the “Long and Steady” hills think Lake and Peak District and the Scotland Highlands.…the ice-age has smoothed the land out into large U-shapes vales and glens which greet you with hills that are long and require a more sustained effort.


To avoid burning yourself on this type, it is crucial to get into a gear that suits your pace and preferred cadence, ie the pedal speed that you can sustain for a long period.


Let’s take a few minutes to consider Cadence.


There is no right or wrong; cadence is to a large extent determined by whether you are blessed with fast twitch muscles (as in sprinters) or slow twitch muscles as in endurance athletes. As an aside your endurance training will convert fast twitch to slow twitch, but the other way is open to debate.


As a general observation with new cyclists, they tend to cycle preferring a very hard gear, grinding away, thinking that they are putting lots of power through wheels and that is the best way to go, but really, to be honest, that is, and no offence meant, it is poor technique.


Think of it being analogous to weight training. When lifting very heavy weights, you can only do so many reps before you are done. It is the same with cycling, once you have fatigued your muscles, even with all the will in the world, you are toast and with an endurance event you may perhaps have another 50 miles to go that day. If you have depleted your glycogen stores (ie all your matches as I mentioned earlier) it can take several days to recover.


To counter this, and again think of weight training, by lifting light weights, you can do a whole lot more reps without muscle fatigue and end up cumulatively lifting more weight in total than if you had started near the maximum you could lift in one go.


There is no “perfect” cadence, for example the likes of Chris Froome use a very high cadence, whereas the average professional cyclist has a cadence usually between 90 to 100 rotations per minute....if you are at say 70 to 80 rpm, then you are in the right ballpark; but if you are at say 50rpm then please consider increasing this as part of your preparation……doing a workout using cadence drills (ie a series of intervals where you spin at a predetermined high rate, either on the flat if cycling or on a turbo with the resistance set very); it is a great way for your legs to get used to spinning at higher speeds.


A word of advice though, unless you are a trained athlete do not aim for 90rpm as this will unnecessarily increase your heart rate with little overall gain.


The way to find your perfect cadence is to use lower (i mean easier) gears that you normally do....and see how that feels. That way you are using your aerobic fitness and not straining your muscles; nine days in the saddle, with several nasty hills of both type; if you can train yourself to use a slightly higher cadence, the whole process of gear shifting becomes smoother and you avoid grinding or even walking your way up those last few hills of the day.


So, how do we build a good cadence ?


If you find that your natural cadence is 40 or 50 rpm, change gears and spin at 70 then 80 then 90 rpm on a flat and see if you can maintain that range on a rolling road without steep hills (use your gears to keep the cadence constant). Practise on each ride shifting the gears until you are in a high cadence, but not too high that very quickly becomes uncomfortable or your hips start to rock. Quick bursts of 100 to 115 rpm is good.


Once you have mastered riding on rolling roads with an average of say 70 rotations per minute, go on the same road and this time change up and up again until you hit 100rpm and stay there for a minute, see how you feel. Change down until it feels more comfortable, practise these drills until you get the feeling what is right for you.


No-one expects you to be riding at a average of 90 rpm, but it it is quick way to test your aerobic fitness (remember VO2Max from Part 1 ?).


However, if you are crushed and unable to continue at that pace after a few minutes on a flat road you will know you need to concentrate your training time on aerobic capacity. But when do you know when it is good ?


A indicator of when your aerobic fitness is good is the degree of what is called aerobic decoupling. When riding at a steady pace (or power) you will find that after a while your heart rate starts to increase even though you are maintaining the same pace (or power), or to keep your heart rate the same you need to lower your pace. Check this out on a long, mainly flat ride, say 3 or 4 hours by recording your speed and heart rate (though comparing heart rate and power is better for cycling because it removes changes of pace due to hills). If the drop in pace, or increase in heart rate in comparison to the other is more than 5% you need to continue to build aerobic capacity. Let me know if you need more information on this, i can take you through it again off line).


So be as economical as you can and rely on your aerobic and anaerobic fitness rather than muscular strength alone....endurance events is very different to your Sunday rides, you must not fatigue your muscles or burn all your matches, they have to last the distance.
I’ll leave this topic with one last observation; I use an electronic gear changing system, which is linked to my cycling computer and records the number of gear changes i do on rides.


So earlier in April i went on a nice 80 mile ride, quite flat, a few rolling hills, perhaps something similar to your day 4. I recorded that I changed gears over 950 times in just under 5 hours, so that is a change of gear every 20 seconds, simply to adapt to the rolling road and keep my cadence as steady as I could. The surprising fact is that I changed the front ring 45 times, even though the route had only about 1,000 metres of climbing, simply to keep my cadence within my range. You might think that is extreme, but with practise you will change gear without thought in the same way you do now in your car to keep the revs in the right range….the same principle applies to your legs !


So please remember that cadence is king, and you need to “spin to win”.

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