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Pedal Triangles to Ride Faster © 2003 by Ken Mierke
Improving your pedal stroke efficiency is one of the most effective ways to improve cycling performance. The human body was made to walk and run, not to pedal a bicycle. I have performed or supervised over 6,000 VO2 Max tests. The results clearly and consistently indicate that pedal stroke efficiency is a key limiting factor for performance athletes. For example, an elite cyclist may produce 20% greater wattage than an intermediate, but consume only 8% more oxygen to do so. In other words, the elite is only 8% fitter and the remaining 12% increase in wattage may be attributed to more efficient pedal stroke mechanics.
On a flat road, the momentum of the rider’s weight moving at a fairly high speed will pull him through dead spots in his pedal stroke, so on flat roads a powerful rider with excessive dead spots in his pedal stroke can “coast” through those dead spots. At the slower speeds cyclists use to climb hills, the rider’s momentum is not so great a factor. Gravity tugs continually and, without momentum to smooth over the dead spots, riding speed literally slows between each pedal stroke. Much of the power generated by each pedal stroke is then wasted on accelerating back to the original speed instead of going faster up the hill. If you are stronger on flat rides than on hilly rides, even when taking bodyweight into account, your pedal stroke probably needs some work.
Cyclists are often told to develop a circular pedal stroke. However, the human body cannot produce a perfect 360-degree pedal stroke and even the most efficient cyclists fail to create power anywhere close to evenly throughout the circle. Our research has shown that the greatest pedaling efficiency occurs by imaging pedaling triangles instead of circles. Mentally breaking the pedal stoke down into the downstroke, the backstroke, and the upstroke and attempting to create power in three straight lines, produces the closest to a circular pedal stroke that a cyclist can create. It also yields the greatest wattage for the amount of oxygen consumed. Taking the time and effort to work on each of these three parts of your pedal stroke will pay big dividends on race day.
The Downstroke
Most of a cyclist’s power is derived from the downstroke. Even a very smooth pedal stroke that lacks power in the downstroke is not efficient.
The quadriceps and the gluteus maximus muscles, two of the most powerful muscles in the body, both provide significant power on the downstroke. One key to the downstroke is creating a long power zone by maximizing the period during which these muscles contract simultaneously.
Good cyclists lengthen their power zones at the top of the pedal stroke, applying pressure earlier in the stroke. Less efficient cyclists try to lengthen their power zones at the bottom of the stroke, which only wastes energy. We recommend concentrating on beginning the downstroke at 12 o’clock and driving diagonally down toward 3 o’clock.
Most of a cyclist’s power is released during the down-stroke. This phase of the pedal-stroke, when performed properly, overlaps power output from hip extension (gluteus maximus and hamstrings) and knee extension (quadriceps). Misunderstanding how power should be applied during the down-stroke causes many riders to lose this crucial overlap and overuse the hamstrings.
The second key to the downstroke is unloading pedal pressure before bottoming dead-center. Since the downstroke is such a naturally dominant part of the pedal stroke, cyclists continue to push down even when the crankarm is at the very bottom in the 6 o’clock position. Obviously this does not contribute to propulsion, but it does waste energy as well as causing muscular fatigue and saddle discomfort. While even the best cyclists in the world fail to completely unload at bottom-dead-center, efficient cyclists come closer than less-skilled cyclists. Working on this skill reduces wasted energy. Transferring smoothly into the backstroke phase of the pedal stroke minimizes energy wasted at bottom-dead-center. The key is attempting to begin the backstroke phase early.
Many cyclists begin the down-stroke late, at about 2 o’clock and direct their power directly downward. This minimizes the overlap of the optimal torque ranges of hip extension and knee extension and may call the hamstrings into play excessively. Since the quadriceps muscles are not activated properly, almost all the power must be produced by hip extension. To accomplish this, the hamstrings must create a very forceful contraction.
In an ideal down-stroke, the power application begins early, at 12 o’clock, and is directed downward diagonally toward 3 o’clock. This activates the quadriceps optimally and lengthens the overlap between the peak-torque production of knee extension and hip extension. The quadriceps and gluteus maximus are the primary power producers and the hamstrings contract moderately.
The Backstroke
A moment of crisis arises during each pedal stroke when the pedals are at the 6 o’clock and 12 o’clock positions and neither leg is engaged in the downstroke. While little power is generated at this point in the pedal stroke, creating as much as possible is critical, especially for climbing. The goal is to provide just enough power to maintain momentum until the next downstroke begins.
Most cyclists don’t really have a backstroke phase, because their downstroke phase lasts too long. We recommend trying to pull your heel back directly through the bottom bracket, beginning at 3 o’clock. Obviously, this movement is impossible, since the crankarms don’t allow it, but attempting it triggers an early backstroke and minimizes wasted energy from pushing down at bottom-dead-center. The downstroke is such a naturally dominant part of cycling that thinking in terms of prematurely pulling straight back actually produces a more circular down/back movement. Attempting to pull back at 3 o’clock will not reduce the power of the latter stages of the downstroke. The leg will, in fact, continue to produce downstroke power well beyond 3 o’clock. However, attempting to begin the backstroke early prevents the downstroke from lasting too long and increases he efficiency of the stroke.
The backstroke is one area of the pedal-stroke where the hamstring muscles should be very active, because only knee flexion provides power in this range. Relaxation during the ranges of the pedal stroke in which the hamstring muscles should not be used heavily (upstroke and downstroke) prevents fatigue and enables powerful backstroke contractions.
The primary pedal-stroke weakness of many riders is extending the down-stroke too long and starting the backstroke late. This prevents the rider from unloading before bottom dead center and causes wasted energy pushing downward when the crankarm is moving directly backward.
The Upstroke
When you were first learning to ride a bike as a kid, what type of pedals did you use? Like everyone else, you used platform pedals, which require different biomechanics than clipless pedals. Have you ever made the effort to learn about the differences?
On platform pedals, how do you keep your right foot on the pedal while your left foot is pushing down? You push down a little bit. This is terribly inefficient, actually using energy and fatiguing the muscles to create negative power. Since you began riding with clipless pedals, have you implemented changes in your power application? Or, like many cyclists, even pretty good ones, do you still pedal the same way you did as a kid, only harder and longer?
At steady riding speeds, even the world’s best riders don’t create power on the upstroke. The difference is that they do not create negative power, while most beginning and intermediate riders do. The goal of the upstroke is to unload the pedal, lifting the weight of the leg, foot, and shoe off the pedal. This allows all of the power generated by the opposite leg’s downstroke to be delivered to the rear wheel and provide propulsion. Most cyclists create negative power during the upstroke, actually allowing the left leg’s downstroke to lift the weight of the right leg, foot, and shoe. This negates some of the power generated by the downstroke.Efficient riders may actually produce significant upstroke power during periods of very hard pedaling, such as on very steep climbs. During steady state riding, however, efficient riders simply lift the weight of their foot, leg, and shoe during the upstroke, but do not create power during this phase. We call this “unloading”. This aspect of pedaling is critical. Consistent unloading on the upstroke is one significant difference between elite and intermediate riders. Without correct unloading, the right and left legs actually fight against each other. The movements of the upstroke are hip-flexion (lifting the knee) and knee-flexion (lifting the foot). Since the hip-flexors are active only in this range of the pedal stroke, they should be the primary muscle contracting during this phase. The hamstrings are very active during the backstroke and somewhat active during the downstroke, so efficient riders relax them during the upstroke. Triathletes must also come off the bike with relatively fresh hamstrings in order to run well.
Attempting to pull up on the pedal through this phase places too much concentration on knee flexion and prevents hamstring relaxation. The hip flexors, once trained, are extremely fatigue resistant. They are only active for about 25% of the pedal stroke. Obviously they can contract fairly powerfully without fatigue when their work to rest ratio is 1:3.
There are two keys to taking advantage of the fresh hip-flexor muscles and resting tired hamstring muscles during the upstroke phase. The first is keeping your concentration on lifting the knee and not the heel or the foot. If a cyclist lifts his knee powerfully, the foot and pedal will follow without contractions to bend the knee. The second key is thinking of the upstroke as a diagonally upward and slightly forward movement, instead of an upward and backward movement. Again, this places the emphasis on the hip-flexor muscles, which should be contracting, instead of the hamstrings, which should be relaxing. When your pedal reaches the seven o’clock position, think of driving your knee up toward the handlebar.
Ken Mierke is head coach of Fitness Concepts (www.Fitness-Concepts.com), developer of Evolution Running (www.EvolutionRunning.com), and author of The Triathlete’s Guide to Run Training.
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Fine Tuning the Cycling Upstroke by Ken Mierke
The racing season is beginning and cyclists are making plans for hard training to make themselves strong enough to race well this year. What is the biggest thing you can do to improve your results this year? More mileage? Longer lactate threshold sets? More climbing or sprinting? You might be surprised that athletes of every level improve more by focusing on economy than any other factor. The race doesn’t necessarily go to the strongest, but to the most efficient.
Many athletes, even advanced ones, should significantly alter technique to perform more efficiently. Fitness Concepts has performed over 6,700 VO2 Max tests (http://www.fitness-concepts.com/voxmax.htm). This test tells how strong an athlete is (VO2 Max) and determines the optimal training intensities (aerobic threshold and lactate threshold), but it also directly measures economy – the amount of energy expended to produce a watt. We have found that 84% of the time, riders had a higher LT wattage more because of economy than because of output. In other words if one cyclist had a lactate threshold wattage that was 10% higher than another, most of the time he/she used less than 5% more energy to do so.
Certainly cyclists need to train hard and smart to make themselves stronger, but there are limits to this. You only have so many hours available to train, your legs can only recover from a certain amount of volume and intensity, and you can’t change your DNA. A serious cyclist (at any level, cat 5 up) who has been training hard for several years will be very high up on his diminishing returns curve for fitness. At this point, it isn’t possible to create huge increases in VO2 Max and lactate threshold energy expenditure.
Cyclists tend to think that beginners need to work hard on pedal stroke mechanics, but “I know how to pedal”. I believe just the opposite. A beginner can improve just by adding an hour a week to his training. The higher the athlete’s level, the more he/she need to look to important details. Michael Jordan knew how to shoot a free throw, yet the greatest player of all time stayed after practice, when the rookies had gone home, to shoot 300 free throws. Perfecting the skill of efficient pedaling is just as important for a cyclist. Lance Armstrong has won the Tour de France six times, and each time he comes back with a different pedal stroke. If Lance’s pedal stroke isn’t good enough yet, yours and mine certainly aren’t.
I coached a category 1 cyclist last year who had won 10 races the year before. This athlete was extraordinarily talented and hard working. When I put him on a bike with Powercranks (training crankarms with a built-in clutch that force the right and left legs to work independently), he couldn’t pedal for 2 minutes without
Very few cyclists pedal correctly on the upstroke, the period of the pedal stroke during which the pedal is rising. Most cyclists relax during this period of the pedal stroke, allowing the right leg’s downstroke to lift the weight of the left leg, foot, and shoe. The two legs fight each other and the upstroke-leg essentially creates negative power – sucking away power created by the opposite leg’s down-stroke. Obviously, this reduces the power that propels the bike, slowing the rider.
The world’s most efficient cyclists unload the pedal on the upstroke. During steady-state riding they don’t actually create power by pulling up, but they avoid creating negative power so that 100% of the other leg’s downstroke goes to propulsion. The muscles that should unload on the upstroke are the hip-flexors, which are located on the front of the upper thigh and hip. These muscles generally have very little endurance and fatigue quickly, so most cyclists just don’t use them enough.
The movement of the upstroke is a combination of hip flexion and knee flexion, so the hip flexors and the hamstrings could both contribute, but using the hip flexors for this phase of the stroke is much more efficient. The hamstring muscles which flex the knee also act as hip extensors, and do so very actively on the down-stroke. The hamstrings contract to flex the knee during the backstroke - the only muscle firing powerfully during this phase. Therefore, if a rider uses knee flexion to accomplish the upstroke, the hamstring muscles are firing throughout the 360 degree pedal stroke without any time to recover. The hip flexors, on the other hand, are active only on the upstroke. Efficient riders rest their hamstrings on the upstroke and emphasize the hip flexors.
Having the rider think of lifting the knee and not the foot, shoe, or pedal on the upstroke is a key. Another is having them think of the upstroke as a diagonally forward/upward movement instead of a directly upward movement. I tell my athletes to drive their knee up toward the handlebar.
While efficient cyclists don’t actually pull up on the upstroke during steady-state riding, they do create power during the upstroke during periods of extremely high torque, such as initiating a sprint, climbing a super steep grade, or accelerating on a climb after upshifting. The hip flexor muscles are extremely powerful, despite their lack of natural endurance.
There are a number of methods of developing the upstroke: Single Leg Drills: Pedaling with one leg clipped out of the pedal for long, steady periods in very light gears at moderate cadence.
Tempo Tension: Pedaling at 50-60 rpm in a gear that will bring heart rate to the middle of zone 3. Concentrate on keeping the down-stroke moderately light and driving the knees up toward the handlebar. Think of the upstroke as diagonally forward and concentrate on lifting the knee, not the foot or pedal.
Strength Training: Many abdominal exercises effectively strengthen the hip flexors and low pulley machines or stretch cords can also be used. Perform some weight training for these muscles with relatively heavy weights and low duration sets to truly build their strength.
Powercranks: Off-season is the perfect time to begin using Powercranks. Powercranks are crankarms designed for training which enable the crank to drive the spindle, but have a clutch built in that keeps the spindle from driving the crank. This forces each leg to perform the upstroke correctly since the clutch prevents the opposite leg’s down-stroke from doing the work. My coaches and clients can get Powercranks at a significant discount at www.FitnessWerx.com.
Concentrating on working the hip flexors and the neuromuscular interactions that trigger their correct use will improve performance next year while giving the quads and glutes athletes an opportunity to rest from the past season. Now is the ideal time to emphasize this part of the pedal stroke to our athletes.
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