Jumping off a fast bike without getting hurt is extremely dangerous and is generally not recommended, as the speed of the body relative to the ground is very high and can easily cause serious injury. If you are in a situation where you have absolutely no safety equipment, it may be helpful to consider the following points, but please understand that these methods are not completely safe: 1. **Choose the right time to jump**: Make sure to jump at a low speed or in a safe environment, such as in an open area or an area without obstacles. 2. **Body position**: When jumping, try to keep your body relaxed and your legs slightly bent, ready for impact when you hit the ground. 3. **Rolling to reduce shock**: Immediately after jumping, try to land in a sideways rolling manner, which can disperse the impact force and reduce the risk of injury. 4. **Practice**: Practicing the action of jumping off a bike at a lower speed can help you better master the technique and response. 5. **Avoid high speed**: Try not to jump at very high speeds, and it is wisest to slow down before jumping. Although some measures can be taken to reduce the risk of injury, jumping off a high-speed bicycle is still very dangerous. It is recommended to use protective gear (such as helmets, knee pads, elbow pads, etc.) and follow the principles of safe riding to ensure your own safety.