We’ve all heard them: running is bad for your knees, you must run daily, your watch is always right.
Let’s separate fact from fiction—backed by science.
Myth 1: Running ruins your knees
Fact: Recreational running does not increase risk of osteoarthritis—some evidence suggests it may even protect joint health.
A systematic review of 24 studies found that running causes only minimal, transient changes in knee cartilage, with no long-term damage in healthy adults.
Researchers also found no consistent difference in the prevalence of knee osteoarthritis between runners and nonrunners; in some cohorts, runners had lower rates of knee pain or surgery.
Takeaway: Running isn’t inherently bad for knees—but sudden jumps in load, poor form, insufficient recovery, or preexisting injury can increase risk. Slow, structured progression and strength work are your allies.
Myth 2: You need to run every day to get benefits
Fact: Training quality and rest often matter more than frequency.
Rest days allow muscles and tendons, as well as the nervous system, to recover. Many marathon plans include 1–2 rest or cross-training days per week.
Overtraining without recovery leads to fatigue, injury, or burnout.
Takeaway: Aim for consistency, not daily volume. A few high-quality sessions + rest trumps daily mediocrity.
Related: 6 Reasons Why You Shouldn’t Run Every Day
Myth 3: If it doesn’t hurt, you’re not working hard enough
Fact: Hard effort doesn’t always equate to pain.
Many runners equate “no pain = no gain,” but pain is often a warning signal—not a sign you’re training hard enough. Instead, use measurable metrics (pace, heart rate, RPE) and listen to bodily cues.
Takeaway: Use training zones and recovery metrics rather than chasing discomfort.
Myth 4: You have to race to call yourself a runner
Fact: Running is a personal journey. You don’t have to chase finish lines or collect medals to earn the title of runner.
Many train for fitness, stress relief, or joy. Your identity as a runner isn’t validated by race results—but if you choose to race, it’s just another way to celebrate progress.
Takeaway: If you lace up and hit the road or trails with purpose, you are a runner.
Myth 5: Only thin bodies are built for running
Fact: People of many body types run and perform well.
Elite and recreational running includes athletes of all shapes and sizes. Fat mass can be a disadvantage in some metrics (e.g., speed relative to bodyweight), but body composition doesn’t preclude enjoyment or even high performance.
Takeaway: Focus on movement and sustainable progress—not a body ideal.
Myth 6: More mileage always means better performance
Fact: Beyond a point, extra volume yields diminishing returns and higher injury risk.
Studies of injury incidence in beginner and recreational runners show that risk increases when training load jumps too much. Also, a large new study suggests abrupt spikes in single-run distance (vs weekly totals) drive many injuries.
Balanced training—mixing easy runs, speed sessions, long runs, and cutback weeks—often proves more effective than blindly upping miles.
Takeaway: Increase volume conservatively (e.g., ≤ 5–10 % per week), monitor feedback, listen to your body, and don’t neglect recovery.
Myth 7: Running on a treadmill is easier and doesn’t count
Fact: Treadmill running does count—and can be just as tough.
Research shows that treadmills with cushioning reduce plantar force but increase metabolic energy consumption.
Biomechanically, running on a treadmill differs slightly, but carries many of the same physiological effects.
Takeaway: Use treadmill runs when needed; if you want harder stimulus, add incline or intervals to compensate.
Myth 8: More cushioning prevents injuries
Fact: Cushioning in running shoes helps comfort, but doesn’t guarantee injury prevention and may encourage sloppy form.
One intervention study found runners randomized to firmer shoes were less likely to be injured than those with more cushioning. Excess cushioning may reduce proprioceptive feedback, causing heavier landings.
Takeaway: Choose footwear that fits your biomechanics, needs, comfort, and training style. Prioritize form and load control over “softer is safer.”
Myth 9: Your watch knows best
Fact: Smartwatches provide useful data, but they’re estimates, not gospel.
Devices use algorithms to estimate heart rate, VO2, level of fitness, etc. But sensor and GPS errors, individual variability, as well as algorithm assumptions, can lead to misleading outputs. Use them only as guidelines.
Takeaway: Combine watch metrics with how you feel, don’t let a red screen guilt you into a bad workout.
Myth 10: Older runners can’t improve
Fact: Aging brings changes, but your potential to improve doesn’t vanish.
While age influences recovery and physiology (e.g. slower adaptation), masters runners continue setting PRs, especially in longer distances.
Strength training and a solid training plan can offset declines. Research on aging runners shows maintained neuromuscular function and adaptability when training is consistent.
Takeaway: Don’t sell yourself short. Incremental patient progress with good recovery can still yield gains at any age.
