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What If You Had
Super Speed?

Set your speed. Explore the consequences. From physics to daily life, discover what superhuman velocity really means.

Choose Your Speed
100 mph
Faster than a cheetah
100 mph Light Speed

Press Enter to start

⚡ Scenario 1 of 14

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Your Physics Report

Here's what the laws of physics say about running at .

Your Speed Profile

Practical
Reckless
Scientific
Social
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What Is This Experience?

What If You Had Super Speed? is a free interactive thought experiment that explores what life would really be like if you could move at superhuman velocity. Through 14 branching scenarios, you make choices about how super speed would affect your commute, your diet, your relationships, your career, and the laws of physics themselves. At the end, you receive a personalized Speed Profile that reveals what kind of speedster you would be.

At Mach 1 speed, air friction would heat your skin to over 160°F — runners would need heat-resistant suits.

How It Works

Start by choosing your speed level, from 100 mph (faster than a cheetah) all the way to the speed of light. Then face 14 scenarios spanning daily life, physics, sports, relationships, adventure, and career. Each scenario includes a real physics fact at your chosen speed. After all scenarios, a physics calculator reveals the real-world consequences of your speed: air friction temperature, caloric requirements, time dilation, and more. Finally, your choices determine your Speed Profile from eight possible personalities.

Frequently Asked Questions

What would happen if humans could run at light speed?
At light speed, time dilation would mean time nearly stops for you while the world ages. You would also need infinite energy according to Einstein's theory of relativity. The air in front of you would be compressed into plasma, and your mass would approach infinity. In practice, light speed is a theoretical upper limit that no object with mass can truly reach.
How many calories would super speed burn?
At 100 mph, a human would burn roughly 10,000+ calories per hour due to the massive energy expenditure of rapid muscle contractions and wind resistance. At higher speeds, the energy requirements become astronomical. At Mach 1, you would need to consume the caloric equivalent of hundreds of meals per hour just to sustain your metabolism.
Could you run on water with super speed?
Yes! At speeds above about 67 mph, surface tension would support a human's weight, allowing you to run across water like a basilisk lizard. The key is maintaining enough downward force through rapid footfalls while moving forward fast enough that you do not sink. Scientists have calculated the exact speed and stride frequency needed to make this work.

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Last updated: April 2026