Flexibility is how far a muscle can lengthen, often with help from gravity or your hands. Mobility is how much of that range you can actively control. Good movement needs both: range plus strength within that range.
Step by step
- Test passive range: lying on your back, use a strap to lift one straight leg.
- Test active range: lift the same leg without help.
- The gap between the two shows where active mobility work helps.
- Train both with stretching and controlled strengthening at end range.
Common mistakes
- Only stretching passively and never strengthening the new range.
Your practice
- Do the strap and no-strap leg lift test and note both heights.
Safety note: Move within a comfortable, pain-free range and breathe throughout. This lesson is general fitness education, not medical advice. If you are pregnant, recovering from an injury or surgery, or have a heart, blood-pressure, joint or other health condition, check with your doctor before you start. Stop and seek medical help if you feel chest pain, dizziness, faintness or unusual shortness of breath.