Cycling Speed: Is 28 mph Fast? Context, Factors, Demands, and Training

Is 28 mph Fast on a Bike?

Yes, 28 mph (45 km/h) is unequivocally a fast speed on a bike for the vast majority of cyclists and in most contexts. It represents a significant level of physiological output and aerodynamic efficiency, pushing beyond recreational paces into the realm of advanced training or competitive efforts.

The Nuance of "Fast": Defining Speed in Cycling

The perception of what constitutes "fast" on a bicycle is highly subjective and context-dependent. A speed that feels blistering on a mountain bike trail might be a moderate pace for a professional time trialist on a perfectly flat course. To properly assess 28 mph, we must consider the typical speeds achieved across different cycling disciplines and rider abilities.

• Average Recreational Rider: For someone cycling for leisure or fitness without specific training, average speeds typically range from 10-15 mph (16-24 km/h) on flat terrain.
• Trained Enthusiast/Club Rider: A rider with regular training, participating in group rides or local events, might average 18-22 mph (29-35 km/h) over an extended period.
• Competitive Cyclist/Racer: In races or high-intensity training, sustained speeds can reach 25-30 mph (40-48 km/h), with sprints often exceeding 35 mph (56 km/h).
• Professional Cyclist: Professionals maintain incredibly high average speeds, often 28-30 mph (45-48 km/h) for hours in flat stages of grand tours, and much higher in sprints or downhill sections.

Against these baselines, 28 mph stands out as a speed that requires considerable effort and skill for nearly any rider.

Factors Influencing Cycling Speed

Achieving and maintaining 28 mph is a complex interplay of several key factors:

• Rider Physiology and Training:
  • Power Output: The primary determinant. A higher functional threshold power (FTP) and peak power output allow for faster speeds.
  • Cardiovascular Fitness: A strong aerobic engine (high VO2 max) is crucial for sustaining high power.
  • Muscular Endurance: The ability of muscles to repeatedly contract efficiently without fatiguing.
  • Body Composition: Lower body fat percentage and optimal muscle mass contribute to a better power-to-weight ratio.
• Equipment and Technology:
  • Bike Type: A road bike, especially an aerodynamic or time trial (TT) bike, is designed for speed on pavement. Mountain bikes or casual cruisers are not.
  • Aerodynamics: Aero frames, wheels, handlebars, and even helmets and clothing significantly reduce drag, which becomes the dominant resistive force at higher speeds.
  • Weight: While less critical than aerodynamics on flat terrain, a lighter bike and rider are advantageous, especially on climbs.
  • Tires: Low rolling resistance tires, properly inflated, reduce friction with the road.
  • Gearing: Appropriate gear ratios allow the rider to maintain an optimal cadence at high speeds.
• Environmental Conditions:
  • Wind: A headwind can drastically reduce speed, while a tailwind can make 28 mph feel effortless. Crosswinds impact stability.
  • Terrain: Flat or slightly downhill terrain is necessary to sustain 28 mph. Uphill gradients make it exceptionally difficult or impossible for most.
  • Road Surface: Smooth asphalt allows for higher speeds than rough pavement, gravel, or dirt.
• Route Characteristics:
  • Solo vs. Group Ride: Drafting behind other riders in a group can reduce power output by 20-40% at high speeds, making 28 mph much easier to sustain.
  • Corners and Traffic: Frequent stops, turns, or traffic congestion will prevent sustained high speeds.

28 mph in Context: A Deep Dive

Let's break down what 28 mph means across different scenarios:

• For the Average Recreational Rider: Sustaining 28 mph for more than a very brief sprint is likely beyond their current physiological capacity. Achieving it even momentarily would feel like an all-out effort.
• For the Trained Cyclist/Enthusiast: 28 mph would be considered a very strong pace. It might be sustainable for short to moderate durations (e.g., 10-30 minutes) as a high-intensity tempo or threshold effort, or for longer periods in a fast-paced group ride while drafting. It's a speed often targeted in competitive training.
• For the Elite/Professional Cyclist: While a professional can sustain 28 mph comfortably for extended periods, it's typically a solid training pace rather than a race-winning speed for sustained efforts. In flat professional races, average speeds often exceed this, especially with the benefit of a peloton.
• Specific Disciplines:
  • Road Cycling (Solo): Extremely fast for a solo rider over any significant distance. Requires high power output.
  • Road Cycling (Group): A challenging but achievable pace in a well-drilled group, especially with drafting.
  • Time Trials: A very competitive speed for an amateur time trialist, often placing them high in local races.
  • Commuting: Exceptionally fast and potentially unsafe in most urban commuting environments due to traffic, pedestrians, and road furniture.
  • Mountain Biking: Practically impossible to sustain on technical trails. Only achievable on very smooth, hard-packed fire roads or significant downhill sections.

Physiological Demands of Maintaining 28 mph

Sustaining 28 mph demands a substantial physiological effort.

• Power Output: The exact power required varies significantly based on rider weight, bike weight, aerodynamic efficiency, and wind conditions. However, a rider of average weight (70-80 kg) on a road bike in a moderately aerodynamic position on flat ground with no wind would likely need to generate 300-400+ watts to maintain 28 mph. This is a high-intensity output for most individuals.
• Energy Systems: At 28 mph, the body primarily relies on its aerobic energy system for sustained power, utilizing oxygen to break down carbohydrates and fats. However, the intensity is high enough that the anaerobic energy system will also be significantly engaged, especially for surges, maintaining speed over small rises, or battling headwinds. This means lactate production will be elevated.
• Heart Rate and Perceived Exertion: Maintaining 28 mph would typically put a rider's heart rate into their Zone 4 (Threshold) or Zone 5 (VO2 Max), indicating a very hard to maximal effort. Perceived exertion would be high, often 8-9 out of 10.

Training Strategies to Achieve and Sustain Higher Speeds

For those aspiring to reach or consistently hold 28 mph, a structured training approach is essential:

• Structured Interval Training: Incorporate intervals at or above your Functional Threshold Power (FTP) to improve your ability to produce and sustain high power outputs.
  • Sweet Spot Training: 88-94% of FTP for durations of 10-30 minutes.
  • Threshold Intervals: 95-105% of FTP for 5-20 minutes.
  • VO2 Max Intervals: 106-120% of FTP for 2-5 minutes.
• Endurance Rides: Build a strong aerobic base with longer, steady-state rides at a moderate intensity.
• Strength Training: Focus on compound movements that target the glutes, quadriceps, hamstrings, and core. Examples include squats, deadlifts, lunges, and plank variations.
• Aerodynamic Position and Bike Fit: Optimize your position on the bike to reduce drag. A professional bike fit can yield significant speed gains for the same power output. Practice holding an aerodynamic tuck.
• Group Riding Skills: Learn to draft effectively to conserve energy and maintain higher speeds in a group.
• Nutrition and Recovery: Proper fueling before, during, and after rides, combined with adequate rest, is crucial for adaptation and performance.

Safety Considerations at High Speeds

Riding at 28 mph significantly increases the risks associated with cycling.

• Reaction Time and Braking Distance: Both are severely impacted. At 28 mph, you cover approximately 41 feet (12.5 meters) per second. This leaves very little time to react to hazards, and braking distances are substantially longer than at lower speeds.
• Road Hazards: Potholes, gravel, debris, and uneven surfaces become much more dangerous, potentially leading to loss of control or punctures.
• Traffic and Pedestrians: The speed differential between a cyclist traveling at 28 mph and other road users or pedestrians is much greater, increasing the risk of collisions. Situational awareness must be exceptionally high.
• Protective Gear: A properly fitted helmet is non-negotiable. Bright clothing and lights (even during the day) enhance visibility.

Conclusion: The Relative Nature of Speed

In summary, 28 mph on a bike is objectively fast. It's a speed that demands high physical fitness, a well-tuned bike, and favorable conditions for most riders to achieve and certainly to sustain. It pushes beyond the realm of casual cycling into serious athletic endeavor. While an elite professional might view it as a strong training pace, for the vast majority of cyclists, hitting 28 mph is a testament to significant training, dedication, and skill, placing them firmly in the upper echelons of cycling performance.