Many athletes are, quite understandably, sceptical as to the benefits of strength training for endurance sports. Sportifs and marathons require continuous exertion over an extended period of time, sometimes up to several hours, at a relatively low percentage of maximum effort. Strength training, conversely, takes place over an extremely short period of time (usually a matter of seconds) at a high percentage of maximum effort. How then can a form of training that so poorly mimics the demands of the other be of any use?
Power to Weight Ratio
The answer to this question lies in understanding the impact strength training can have on your power to weight ratio, the importance of which is familiar to most competitive cyclists and distance runners.
Like a Rocket Strapped to a Feather
In this instance power refers to the amount of force you can apply to the pedal or floor in the time you have available to apply it (i.e. when your foot is in contact with the ground or your pedal is in the optimal position to produce the highest level of torque) and weight refers to the weight of you/you and your bike. The fastest athlete will be able to produce great amounts of power with each step or pedal stroke while having relatively little mass to propel along. Like a rocket strapped to a feather as opposed to a lead brick. So if two athletes of different weight (or mass) produce the same amount of power the lighter of the two will be faster.
Go on a Diet!
The first method of improving this ratio is to look at the weight aspect. So go on a diet or buy a lighter bike!
The obvious problem with this approach is that you cannot completely eliminate the weight of yourself or your bike. Accordingly at some point it makes sense to tackle the other side of the equation and increase your power (the equivalent of putting a bigger engine in your car).
Power = Force x Velocity. The athlete that produces the greatest amount of power will be the one who applies the most amount of force as quickly as possible. A stronger muscle can exert more force (against the pedal or floor) and with proper training can be taught to apply that force extremely quickly, i.e. in the short window you have available during each revolution or foot step.
On Your Bike
In his excellent blog “Sensible Cycling”, Danny Beveridge has calculated that an average A grade cyclist will exert 46kg of force per pedal stroke over the course of a time trial.
Let’s say this hypothetical cyclist is capable of producing 100kg of force with each leg in a single all-out effort (this would be his 1 rep max or “1RM”). He is therefore asking his legs to produce multiple repetitions (pedal strokes) of 46% of his 1RM (on average) for the duration of the race.
Now let’s say that, through strength training, the cyclist in question increases his 1RM per leg from 100kg to 150kg. This will have two potential effects:
1) With the ability to exert 150kg as opposed to 100kg of force on the pedal, producing a repeated effort of 46kg now requires just 30% of his maximum force potential as opposed to the previous 46%. This will make each pedal stroke relatively easier and therefore less of an effort to sustain over the course of the race
2) If the cyclist continues to work at 46% of his 1RM for the duration of the race he will be exerting an average of 69kg of force per pedal stroke, which if the same cadence is maintained will obviously translate into a faster pace and a better race time.
For endurance runners the benefits of strength training are also significant. As with cycling a stronger muscle will require a lower proportion of its maximal force potential to move your body weight forward with each step, requiring less energy and therefore better fuel economy!
A second speed enhancing benefit to improving the strength and power in your legs is an improvement in stride length. A more powerful leg will put more force into the ground propelling you a greater distance with each step meaning fewer steps will now be required to cover the same distance.
A Study by the University of New Hampshire showed that a 10 week strength training program improved running economy by 4% (running economy is essentially the same as a cars fuel economy, that is the distance they can cover on a given amount of fuel). That may not sound like a huge amount but it translates into a 96 second improvement on a 40 minute 10k time! It’s worth mentioning that the strength training protocol used in this study wasn’t particularly sophisticated and even greater improvements could be expected with better programming.
Do it Right
The concern many people have with regards to strength training for endurance benefits is the potential for increased muscle growth and with it associated weight gain. This can be negated through the application of proper training methods designed to develop the strength and power of your existing muscle as opposed to increasing the muscle size.
How to #BeMoreAwesome
If you would like help with increasing your strength for endurance sports contact Will or just drop in to Plymouth Performance Gym.