According to a massive RunRepeat study based on over 34 million race results, the average running times are:

• 35 minutes for a 5K
• One hour and two minutes for a 10K
• Two hours and 14 minutes for a half-marathon
• Four hours and 26 minutes for a full marathon.

We should keep in mind that the data is collected from race results. It doesn't mean every runner is racing or running as fast as they can.

Any numbers regarding the maximum running speed of humans are mostly speculation.

Because Usain Bolt holds the title of the world's fasted runner, we can assume that his top speed of about 28 miles per hour is as fast as humans can run. But scientists believe humans may be able to run at a speed of up to 40 miles per hour. A 2010 study using computer models show that based on the pounds of force that human muscle fibres can withstand, humans have the potential to run faster.

• Your effort
• Your shoes
• Whether you have any external weight on you, such as a hydration vest
• The terrain you're running on
• The weather conditions
• Your hydration status
• If you had adequate rest the night before
• Your training volume
• The type of training you do. (E.g. weightlifting or cross-training.)
• How much running experience you have
• Genetics and physical factors, such as the length of your legs
• Your mood and the music you listen to can affect your running performance

Run training that can help you become a faster runner:

• Tempo runs help to develop your anaerobic or lactate threshold. Run at an easy pace for five to 10 minutes, then run about 10 seconds slower than your 10K pace for 15 to 25 minutes, then finishing up with another five to 10 minutes of easy running.
• Interval runs include segments of fast running followed by segments of easy running or walking.
• Fartlek runs are like interval running, except that it's based more on how you feel.

• Hill runs. Running up and down hills helps to strengthen your legs and lungs.
• Trail runs allow for a varied terrain that can make you a faster runner on roads.
• Distance runs sprinkled here and there will improve your endurance.
• Sprinting sessions once or twice a week can improve your speed.
• Easy runs help you to adapt to all the training you are doing.