Rucking 101: Why Walking with Weight is the Ultimate Low-Impact Cardio

# Role
Fitness Expert and Experienced Rucking Enthusiast

# Context
You are writing a comprehensive guide on "Rucking 101" for beginners who are interested in learning about this low-impact cardio exercise. The target audience is generally healthy adults of varying fitness levels looking for an accessible and effective workout.

# Task
Write a fitness guide about rucking, focusing on the following:

1.  **Introduction:** Briefly define rucking (military-style walking with a weighted backpack) and its increasing popularity.
2.  **Calorie-Burning Benefits:** Explain how rucking can be an effective way to burn calories and improve cardiovascular health. Provide an estimated calorie burn range per hour, considering factors like weight, pack weight, and pace.
3.  **Proper Posture and Technique:** Detail the correct posture and walking technique to avoid injuries. This includes advice on backpack fit, stride length, and core engagement. Include visuals or explain how the posture should look.
4.  **Getting Started:** Provide a step-by-step guide on how to start rucking with minimal equipment. This includes:
    *   Choosing a backpack.
    *   Using bricks or other household items as weight.
    *   Starting with a light weight and short distance.
    *   Gradually increasing weight and distance over time.
5.  **Safety Considerations:** Include important safety tips, such as hydration, appropriate footwear, and listening to your body. Mention signs of overexertion and when to consult a doctor.
6. **Progression & Goal Setting**: Explain how to set achievable goals with rucking and how to track your progress. Include strategies for increasing the challenge over time, such as adding weight, increasing distance, or incorporating hills.

# Constraints
*   The guide should be informative, encouraging, and easy to understand for beginners.
*   Use a friendly and approachable tone, avoiding overly technical jargon.
*   Emphasize the accessibility and low-impact nature of rucking.
*   The guide should be approximately 500-700 words in length.
*   Do not provide specific medical advice; instead, encourage readers to consult with a healthcare professional.

# Output Format
Markdown format, including:

*   A clear and concise title: "Rucking 101: Why Walking with Weight is the Ultimate Low-Impact Cardio"
*   Headings and subheadings for each section.
*   Bulleted lists for the "Getting Started" and "Safety Considerations" sections.
*   Estimated calorie burn range.