Road Biking




General Principles


Races


Road Racing





  • Stage races: Multiday races over consecutive days with daily stage winners and an overall winner based on cumulative time; mass start races where the athletes ride in a peloton.



  • Grand tours: Tour de France, Giro d’Italia, and Vuelta a España; usually include a prologue, flat stages for “sprinters,” hilly stages for “climbers,” and time trials



  • Road races: Mass start point to point races between 100 km and 298 km in length (Milan–San Remo, the longest professional 1 day race in modern times)



  • Circuit races: Multilap races of 100 km to 140 km, on 5-km to 30-km courses. The World Championship and Olympic road races are circuit races. A kermesse is a common cycling race type in Belgium for amateurs, lasting for 120 to 180 minutes.



  • Criteria: Multilap races of 40–80 km or miles, on 1-km to 1-mile courses containing tight cornered roads. A common cycling race for amateurs in the United States (US), lasting for 60 to 90 minutes. Crashes are common.



  • Time trials (TT): Individual races “against the clock”; riders start at 1- to 2-minute intervals on time trial bikes. Drafting is prohibited. Distances range from 20 km to 50 km. Triathlons have TTs in lengths from 20 km (sprint distance) to 180 km (full distance).



Track Racing





  • Description: Held on a velodrome track (with banking, length 250 m to 333 m); riders use track bikes (with no brakes and fixed gears)



  • Races: Match sprint, kilometer, pursuit, team pursuit, points race, miss and out, keirin, Madison



Touring





  • Self-contained noncompetitive cycling for pleasure, ranging from a day to multiday trips



  • Fully loaded or self-supported touring involves cyclists carrying everything they need—clothing, food, cooking equipment, and tents in panniers



  • Cyclosportive (randonnee cyclosportive), or cyclosportif, is a long-distance, annual, organized, mass-participation cycling event.



  • The Italian term Gran Fondo is used to name these events in the US.



  • The true Italian Gran Fondos are long-distance bicycle races, while in the US, they refer to something in between a race and a tour: a mass participation ride of varying distance on open roads, with some racing for time.



  • Both a cultural and a sporting event



Riders





  • Sprinters: Possess high numbers of fast-twitch muscle fibers for explosive acceleration; can reach speeds of 66.1 ± 3.4 kph (57.1 to 70.6), with peak power output of 1248 ± 122 W (989 to 1443 W). Sprinters take calculated risks in maneuvering through the pack, waiting until the last possible moment to move out of another rider’s slipstream and into the wind. Professional sprinters in the last 10 minutes of a race produce 316 ± 43 W, 95 ± 4 rpm and speeds of 50.5 ± 3.3 kph; in the last minute prior to the sprint produce 487 ± 58 W, 102 ± 6 rpm and speeds of 55.4 ± 4 kph; with peak power during the sprint at 17.4 ± 1.7 W/kg



  • Climbers: Lightweight, possessing high levels of aerobic power, a high power-to-weight ratio, a V̇O 2 max of 75 to 85 mL/kg/min, and power output measurements of 7.4 W/kg over 5 minutes, 6.5 W/kg over 20 minutes, 6.1 W/kg over 30 min, and 5.7 W/kg over 1 hour



  • Lead out riders: Break the wind for their sprinters until the very last possible moment by sustaining high speed for a kilometer; generally lack the finishing top end speed of sprinters



  • Time trialists: Ride at a steady state for long periods; physically larger cyclists who can push a big gear and produce greater absolute power outputs



  • Team leaders: Riders for stage race overall classification must be able to climb and time trial.



  • Domestiques: Sacrifice themselves for the sprinters and leaders by carrying water, blocking the wind, or even giving a wheel



Organizations





  • USA Cycling ( USAC): National governing body for bicycle racing in the US



  • Union Cycliste Internationale (UCI): World governing body for cycling. Issues licenses, enforces disciplinary rules, manages the classification of races and points ranking systems, and oversees the World Championships.



  • International Olympic Committee (IOC): Organization that oversees the Olympics



  • United States Anti-Doping Agency ( USADA ) : A nongovernmental agency responsible for implementation of the World Anti-Doping Code in the US. The World Anti-Doping Code, which lists drugs and methods that are prohibited in sports, was developed by the World Anti-Doping Agency (WADA).



  • WADA: Independent foundation created through a collective initiative led by the IOC. In November 1999, the WADA was created to promote and coordinate the fight against doping in sports. In 2004, the World Anti-Doping Code was implemented by sports organizations prior to the Athens Olympics, standardizing regulations governing antidoping.



  • Court of Arbitration for Sport (CAS): International institution independent of any sports organization to facilitate the settlement of sports-related disputes through arbitration or mediation.



  • Mouvement Pour un Cyclisme Credible (MPCC): A union created on July 24, 2007 by professional road cycling teams to defend the idea of clean cycling according to a strict code of ethics.



Epidemiology and Injury Statistics





  • Traumatic injuries occur in 38% to 48.5% of professionals.



  • Overuse injuries occur in 51.5% to 62% of professionals.



  • Two-thirds of traumatic injuries involve the upper extremity.



  • Two-thirds of overuse injuries involve the lower extremity.



  • Touring cyclists on a 500-mile, 8-day ride, sustained 57.2% bicycle contact injuries (32.8% buttock, 9.1% groin, 10% palmar, 5.3% foot) and 42.8% overuse injuries.



  • A 4-year study of 51 top level professionals found that 43 athletes sustained 103 injuries (50 traumatic and 53 overuse). eight remained free of injury, 22 (43%) sustained both traumatic and overuse injuries, 13 (25.5%) sustained only traumatic injuries, and 10 (19.5%) sustained only overuse injuries. Twenty-nine (67.4%) sustained more than one injury.



  • A survey of 81 cyclists in a well-established masters cycling club found:




    • 81% had a racing license; average number of racing years 9.5, with an average annual mileage 6,000 miles.



    • 79% were seen in an emergency room, 33% had been admitted to hospital, with 15% to the intensive care unit.



    • 54% had sustained fractures: clavicle, 22 cyclists; upper extremity, 20 cyclists; ribs, 20 cyclists; lower extremity, 11 cyclists; vertebral, 11 cyclists; pelvis, 6 cyclists; skull, 6 cyclists.



    • 45% reported a head injury; 34% reported a concussion, with 9% reporting more than one.



    • 75% reported breaking one or more helmets from a crash.



    • 90% reported having road rash.



    • 37% of crashes involved motor vehicles, 9% were due to road surface hazards, 12% were due to skill errors, and 10% were due to mechanical problems.



    • 17% occurred in a paceline, 12% in racing, often criteriums.




Equipment and Safety Issues





  • Bicycles should be inspected regularly. Tire pressure should be set at the proper amount; lower in wet road conditions.



  • Protective gear:




    • Helmets manufactured after 1999 must meet the Consumer Product Safety Commission (CPSC) standard by law to be sold in the US. There is no federal law in the US requiring bicycle helmet use. Presently, 22 states, including the District of Columbia, have mandatory helmet laws. Helmets are designed for one crash only. Cyclists should write their name, contact information, and medical information in the helmet for emergencies.



    • Protective clothing: gloves, snug-fitting cycling wear, chamois padding in shorts, and sunglasses




Biomechanical Principles


Bicycle Anatomy


Road Bicycle





  • Key frame measurements are seat tube length, seat tube angle, and top tube length.



  • Key component measurements




    • Crank length: Based on height of rider or inseam length ( Table 94.1 ). Too long may predispose rider to fatigue and knee ailments. “Spinning” is easier with a shorter crank.



      TABLE 94.1

      CRANK ARM







































      Height (in) Crank Length (mm) Inseam (in) Crank Length (mm)
      <60 160 <29 165
      60–64 165–167.5 29–32 170
      65–72 170 32–34 172.5
      72–74 172.5 >34 175
      74–76 175
      >76 180

      Modified from Burke ER. High-Tech Cycling, 2nd ed. Champaign, IL: Human Kinetics, 2003.



    • Crankset:




      • Triple (3 chain rings): Large chain ring usually has 52 teeth, medium 39 teeth, and small 30 teeth.



      • Standard (2 chain rings): Large chain ring usually has 53 teeth and small 39 teeth.



      • Compact (2 chain rings): Large chain ring usually has 50 teeth and small 34 or 36 teeth.




    • Stem length and angle



    • Handlebar width should be close to the width of the shoulders.



    • Handlebar tilt: Bars can slip and rotate into downward tilt, which can cause excessive reach, leading to hand, neck, and back symptoms.



    • Gearing: The number of gears on a bike is equal to the number of sprockets on the rear wheel multiplied by the number of chainrings. A double chainring on the front with an 11-speed cassette has 22 speeds. A high or big gear is achieved by riding the larger chainring on the front and a smaller cog on the rear, such as 53 × 11. The smallest chainring combined with the largest cog produces a small gear, used for climbing and spinning. Professionals are efficient in choosing the right gear to maintain a high cadence of 90 rpm or greater while maintaining a high speed for an extended period of time.




  • Key bicycle measurements




    • Saddle height: center of the bottom bracket to the height of saddle where rider sits



    • Difference between saddle height and handlebar height



    • Saddle tilt



    • Saddle fore-aft



    • Plumb line from nose of the saddle, measure the distance behind bottom bracket



    • Distance from nose of saddle to handlebars




Track Bicycle





  • No brakes



  • Fixed gear



  • Major trauma risk with crashes



Time Trial Bicycle





  • Steeper seat tube angle (78 to 84 degrees), aero bars, aero deep dish wheels or rear disc



  • Designed to go fast and straight



  • Goal is the reduction of frontal surface area, a flat back, narrow arm position, and elbow flexion of 90 to 110 degrees with the ear directly over elbow. The “Praying Mantis” and “Superman” positions are aero set ups, both banned by the UCI.



  • The narrow positioning of the arms does not restrict oxygen consumption and lung function.



Bike Fit





  • A proper fit is essential for rider comfort, safety, injury prevention, and peak performance.



  • The goal is the optimization of power and aerobic efficiency while avoiding injury ( Table 94.2 ).



    TABLE 94.2

    OVERUSE INJURIES: CONTRIBUTING BICYCLE POSTURE AND BICYCLE ADJUSTMENTS








































    Ailment Contributing Position Bicycle Adjustment
    Posterior neck pain, may extend to head Too great of a reach, handlebars too low, too stretched out Ride more upright to shorten reach
    Raise stem height
    Shorten stem length
    Ride with hands on hoods or tops of bars
    Scapular pain Too great of a reach, handlebars too low, too stretched out Ride more upright shorten reach
    Raise stem height
    Shorten stem length
    Ride with hands on hoods or tops of bars
    Hand neuropathy (cyclist’s palsy) Too much pressure on bars, handlebars too low, saddle too far forward, excessive downward saddle tilt Increase padding on bars and gloves
    Avoid prolonged pressure, change hand position often
    Raise stem height
    Move saddle back if too far forward
    If saddle is tilted down, position it level
    Low back pain Too stretched out Ride more upright to shorten reach
    Raise stem height
    Shorten stem length
    Tibialis anterior tendinopathy Saddle height too high Lower saddle height
    Achilles tendinopathy Saddle height too high (excessive stretch)
    Saddle height too low (with concomitant dropping of heel to generate more power)
    Lower saddle height
    Raise saddle height
    Morton’s neuroma/foot pain/numbness Cleat position
    Irregular sole
    Shoes too tight
    Usually, move cleat back, but may be forward
    Check sole for inner wear or cleat bolts pressing inward
    Wider shoes, loosen Velcro straps/shoe buckle
    Perineal numbness Saddle too high
    Tilt angle excessively up or down
    Lower saddle height
    Adjust angle closer to level with the ground

    From Baker A. Medical problems in road cycling. In: Gregor RJ, Conconi F, eds. Road Cycling. Oxford: Blackwell Sciences, 2000, pp 18-45; and Silberman M, Webner D, Collina S, et al. Road bicycle fit: practical management. Clin J Sport Med . 2005;15(4):271-276.



  • Fit can be tested using static (at rest) or dynamic (while riding) measurements. Dynamic fit testing may involve video analysis; heart rate, wattage, pedal torque readings; wind tunnel testing.



  • Changes should be made gradually.



  • There are three contact areas where a rider interfaces with the bicycle: shoe–cleat–pedal, pelvis–saddle, and hands–handlebar ( Fig. 94.1 ).




    Figure 94.1


    Road bike fit.



Shoe–Cleat–Pedal Interface





  • The first metatarsal head lies directly over the pedal axle (see Fig. 94.1 ).



  • Leg length discrepancy: shims can be inserted under the shorter leg, or the cleat may be moved forward (and the foot back). One-third to half of the difference should be corrected.



  • Heel lifts and orthotics are not sufficient for cycling because the driving force is primarily through the first and second metatarsal heads. Varus forefoot wedges may be used.



Pelvis–Saddle Interface





  • Saddle height




    • Traditional existing formulas are designed to fit a rider for the most power at minimal aerobic cost.



    • Greg LeMond and Cyrille Guimard formula: rider’s inseam length in centimeters 0.883 × saddle height (see Fig. 94.1 ).



    • Knee angle method: The knee should be flexed 25 to 30 degrees from full extension, with the pedal in the 6-o’clock position (also known as DBC, dead bottom center) (see Fig. 94.1 ).



    • Saddle fore-aft




      • With the pedal positioned at 3 o’clock (KNOPS, knee over pedal spindle), a plumb line dropped from the inferior pole of the patella should hang directly over the pedal axle (see Fig. 94.1 ).



      • Time trialists and triathletes prefer a more forward position so that the plumb line falls in front of axle.



      • Moving the saddle forward lowers the saddle height, whereas moving it backward raises the saddle.



      • To compete in a time trial with aerobars, a rider with one bike may move the saddle slightly forward and higher.



      • Saddle tilt




        • Saddle tilt should be close to level.



        • About 60% of body weight should be centered on the narrow saddle.




      • Time trialists riding on aerobars may prefer a slight downward tilt of the saddle or a saddle with a split nose to relieve pressure on the perineum.





Hands–Handlebar Interface





  • Stem and handlebar height




    • Stem height is a subjective measurement; is important in terms of aerodynamics, power production, comfort, and injury prevention (see Fig. 94.1 ).



    • With the hands positioned on the brake hoods and the arms slightly flexed, the torso should flex to about 45 degrees in relation to a nonsloping top tube.



    • When the hands are in the drops, the torso should flex to about 60 degrees.



    • The vertical distance, or drop, between the top of the saddle to the bars should be about 5 to 8 cm.



    • A recreational rider may prefer to sit more upright with a shorter reach and higher-raised handlebars for comfort.



    • An average-sized male cyclist may decrease his frontal area by 30 degrees, moving from the upright touring position to a racing position.



    • If forward-flexed excessively, the maximal sustainable power may be reduced because of diminished blood flow and/or changes in muscle lengths.



    • Handlebar tilt is a personal preference, but most cyclists prefer the lower curve and brake hoods to be slightly elevated. Bar shape and size also play an integral role in proper fit.




  • Stem length or extension




    • A rider’s reach is determined by the top tube length, stem length, and stem angle or rise (see Fig. 94.1 ).



    • Too short a top tube or stem length, and the rider will be bunched up. Too long, and the rider will be stretched out.



    • A good starting point is: when the rider looks down with the arms slightly bent and the hands in the drops, the front hub should be obscured by the handlebars.



    • If the frame was properly fitted, the top tube length will allow an optimum position to be achieved with the use of a 10- to 12-cm stem.






Training and Physiology


Performance Testing





  • Conconi test: One of the first tests to determine lactate threshold (LT) without directly measuring lactate; the pace at which the linear correlation between heart rate and velocity is lost is called the deflection velocity or deflection point, and is said to occur at the LT; a ramp protocol of increasing watts is performed in the laboratory with measurement of HR; numerous authors have found the Conconi test invalid.



  • Lactate threshold (LT) or anaerobic threshold (AT): There is no consensus definition. The original incorrect hypothesis: the point of exertion where body goes anaerobic or into “oxygen debt” and rapidly produces lactic acid , causing fatigue and leg burn. The onset of blood lactate accumulation (OBLA) was originally referred to as the effort level that corresponded to the point at which lactate began to rise exponentially—a blood lactate level of 4 mmol. Most commonly, LT refers to the effort (watts) that an athlete can maintain without a rise in lactate. The USOC Sport Science and Technology Division identifies the lactate threshold (LT) as the point at which a minimum increase of 1.0 mmol/L above baseline values is followed by another increase greater than 1.0 mmol/L. Maximum lactate steady state (MLSS) : the effort level at which there is an equilibrium between lactate production and clearance, such that prolonged exercise does not result in rising serum lactate. Critical lactate measurements are power output at 2 mmol and 4 mmol. Lactate is a useable fuel, and training helps the body become more efficient at shuttling lactate for utilization to other parts of the body.



  • V̇O 2 max test: Ramp protocol consisting of increasing load by 25 watts at 1-minute increments until athlete failure to maintain set cadence. Measure oxygen consumption and heart rate (HR) at different workloads.



  • Maximum aerobic power test with lactate: Ramp protocol with increasing load of 30 to 40 watts at 3- to 4-minute intervals until failure to maintain set cadence. Measure V̇O 2 , HR, watts, lactate. Maximal aerobic power output (MAP) is defined as the highest power output maintained during the test. Higher power outputs are achieved during shorter ramp protocols of 1-minute stages of 25 watt increments versus 4-minute stages of 35 watt increments. V̇O 2 max values of greater than 70 mL/kg/min are found in elite and professional cyclists. Professional cyclists appear to have a decrease in the magnitude of the V̇O 2 slow component (oxygen uptake slowly rises during prolonged exercise at submaximal intensity, attributed to recruitment of type II fibers due to fatigue of type I fibers).



  • Cycling economy (CE): Power output generated in watts at a cost of 1 L of oxygen per minute of exercise (Coyle). For a constant load test of 20 minutes at 80% of V̇O 2 max, the economy of world class cyclists averages 85 W/L/min.



  • Gross mechanical efficiency (GE): Ratio of work accomplished to energy expended; GE = 60 × W ÷ 20,934 × V̇O 2 (Jeukendrup). For world class cyclists, the GE is 25%. Both CE and GE are positively related to the percentage distribution of type 1 fibers in the knee extensors. Once a high level of fitness has been obtained, such as in the elite athlete, CE and GE performed at submaximal intensities of 70% to 90% of maximum heart rate are more important determinants of cycling performance than V̇O 2 max (Lucia).



  • Wingate anaerobic test (WANT): Developed in Israel during the 1970s and measures peak anaerobic power (highest mechanical power generated during any 3- to 5-second interval of the test), anaerobic fatigue (the percentage decline in power compared with peak power output), and total anaerobic capacity (total amount of work accomplished over 30 seconds); the athlete pedals on a mechanically braked ergometer for 30 seconds all out against a fixed resistance.



Training Periods of Professional Road Cyclists





  • “Rest” (November to December)




    • Weekly average 200 km/week, gentle, easy



    • 90% of the time spent in Zone 1, less than 70% of maximum heart rate (HRmax)



    • 10% of the time spent in Zone 2, 70% to 90% HRmax



    • 0% of the time spent in Zone 3, greater than 90% HRmax




  • Precompetition (December to mid-February)




    • Weekly average 700 km/week; building base mileage, long steady rides, no intervals prior to 1,000 miles



    • 80% of the time spent in Zone 1, less than 70% of HRmax



    • 15% of the time spent in Zone 2, 70% to 90% HRmax



    • 5% of the time spent in Zone 3, greater than 90% HRmax




  • Competition (mid-February to October)




    • Weekly average 800 km/week



    • 75% of the time spent in Zone 1, less than 70% of HRmax



    • 15% of the time spent in Zone 2, 70% to 90% HRmax



    • 10% of the time spent in Zone 3, greater than 90% HRmax




  • Most riders plan for two peaks during the season.



  • Training prescription is traditionally not as precise as in other endurance sports; most build long steady low-intensity mileage in winter months; attend one or two 8 day training camps with higher intensity and mileage in the late winter; “race into shape” with early season races. Traditional programs are followed to prepare riders for grand tours, with generally 30 days of racing prior to Tour de France.



  • With power measurements on the road, cyclists can follow stricter training programs.



Training Measurements





  • Perceived level of exertion: Simply monitoring how one feels. Borg 10- or 20-point scale



  • Time: Measure ride duration only, not intensity. Hours per ride for recreational rider: 1 to 1.5 hours. Amateur: 2 to 3 hours per ride, 8 to 12 hours per week. Professional: 15 to 30 hours per week.



  • Speed: Training based on average speed. Generally a poor indicator of training intensity because of the effects of altitude, wind, terrain, road surface, and drafting. Using average speed as indicator of intensity will lead to overtraining.



  • Distance: Training based on weekly or daily mileage. Does not measure intensity



  • Heart rate: Closely correlates with exercise intensity, power output, or rate of oxygen consumption in the laboratory, correlation not as close out on the roads. Influenced by altitude, heat, hydration, illness, sleep, overreaching, and overtraining. Heart rate responds relatively slowly to changes in exercise intensity and cannot be used to regulate the intensity of shorter efforts (heart rate lag). Heart rate is not a direct determinant of performance but is a reflection of the strain imposed on the cardiovascular system for the level of exertion.



  • Power output: Provides a direct and immediate answer to exercise intensity. Measured on the road with bike-mounted power meter systems. Power at LT, or 4 mmol of lactate, is one of the most important physiologic determinants of cycling performance. Functional threshold power equals average power during a 40-km (50- to 70-minute) time trial. Correlates very highly, slightly greater than, power at LT (defined as 1 mmol/L increase in blood lactate over exercise baseline). Estimates athlete’s threshold power by measuring power athlete can routinely produce in training during long interval repeats of 2 × 20 minutes. Mean power for five mass start stages: 220 ± 22 W (range 190 W to 310 W), average HR: 142 ± 5 beats per minute (bpm). Mean power for uphill 13 km TT: 392 ± 60 W (5.5 ± 0.4 W/kg), average HR: 169 ± 3 bpm. Indirect measurement for 3-week stage races: 246 ± 44 W for high mountain stages, 234 ± 43 W for semimountainous stages, 192 ± 45 W for flat stages ( Table 94.3 )


Jul 19, 2019 | Posted by in SPORT MEDICINE | Comments Off on Road Biking

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