This may sound simple, but it is rarely carried out since most people train in the discipline they enjoy most, not the discipline they need to work on most.
How to improve your bike performance.
After endurance, the most fundamental fitness component for the triathlete to develop on the bike is force. "Hills make you strong for the flats, but flats don't make you strong for the hills."
Force training on the bike is even more important if you are not lifting weights throughout your base and build phases.
Force is the ability to overcome resistance, such as a rider applying power on the pedals. If you develop force on the bike, you will not only be a faster rider, you will also be able to ride longer and push bigger gears.
The idea behind force training is not to improve the force a muscle fiber can generate, but to recruit more muscle fibers when pedaling. In order to achieve this, bodybuilders lift heavy weights very slowly to induce a near maximum contraction for a relatively long time. For triathletes, the same principle is applied, but it relates specifically to cycling.
The best way to generate a near maximum contraction for a long period is to push very big gears at a slow cadence. When staying seated in the saddle while climbing, you will be able to develop even more muscular contraction.
Sport-specific strength work such as force sessions on the bike is most advantageous for the time constrained cyclist who doesn't have time for weightlifting sessions.
Some of the sessions for triathletes are:
Big gear/low heart rate
Do 3-4 x 5 minutes in a big gear while maintaining a heart rate in zone 2 (of 5, with 5 being the most intense; zone 2 approximates "very light" to "fairly light" exertion.). Sit during the intervals as that best develops the fibers.
As with your training, progress the intervals up to 6 x 5 minutes, depending on your fitness level and the amount of these sessions you have done previously. The objective is to tax the muscle fibers, not the heart, thus keeping the heart rate relatively low.
As you get into the build phase of training, this session will progress to taxing both the muscle fibers and heart rate, such as: 4-5 x 6 minutes in a biggest gear possible with a cadence of 75-80 rpm on a flat to rolling course. Do each interval to exhaustion with five minutes' easy spinning recovery.
The 3, 3, 3
Warm up 20 minutes. On a climb (preferably long), do a continuous 3-minute stand (out of the saddle) in big gear, 3-minute sit big gear, 3-minute easy spin in small gear. Don't let your heart rate get above zone 3 ("somewhat hard" perceived exertion) at any time.
Do this up to 6 times through for a total of 54 minutes, depending on length of the ride. Keep your cadence at 65-70 rpm with the exception of the easy spinning segment. Also, as the season progresses, the intensity will increase.
Rep it
Warm up 10 minutes. There are no prescribed zones, as heart rate is not important. In your big chainring and a gear giving you a cadence of 50-60 rpm, every 3 minutes do 15-20 revolutions of max effort. Complete 6-10. Cool down 5 to 10 minutes. This can be done with other force workouts depending on the length of the ride.
Indoor force/hills
With your bike on an indoor trainer, raise the front wheel off the floor 4-6 inches. Warm up 10 minutes, then in zone 4-5 effort with an RPE of 16-19, do 6, 5 and 4 minutes while attacking the last :30 with an all-out effort.
Recovery is half of the interval time. Raising the front wheel helps simulate your position while climbing a hill. Again, the intensity progresses as you become fitter.
Do not attempt any of these sessions if you have knee problems. When doing these sets, focus on maintaining proper form, avoiding excessive upper body movement. Concentrate on efficient pedal stroke technique.
Don't fall into the realm of mashing big gears. Developing force will make you a more powerful rider, and therefore a faster rider. It will also make you more economical on the bike, as at a given intensity, you will need a lower percentage of your maximal strength.
Eventually, because the bike leg of the triathlon will be easier, you will have more energy when running off the bike, and indirectly, your improved bike strength will be beneficial to your run.
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