Article: 1 kg less = ~4 kg less pressure on your knees...and even more when you walk, run, or go down stairs!

By Marc Dellière, Medical Consultant & Trainer – Specialist in Stress, Prevention & Integrative Health

Many people think that the load borne by the knees is simply their weight. In reality, each step multiplies this weight by 2 to 4, depending on the activity!

What the studies say

In vivo measurements (in patients fitted with instrumented prostheses) have shown that:

* When walking, the load on the knee reaches 2.5 to 2.8 times body weight.

* When going down stairs, it rises to 3.1 times body weight.

* When running, it climbs to 3.6 times body weight (or even more depending on speed).

And according to a landmark study from Harvard University:

“Every kilogram of weight loss reduces the pressure on the knee by about 4 kilograms with each step”

Why this multiplier?

With each movement, the body does not support its weight statically: the reaction forces from the ground, bone levers, and the action of the quadriceps muscles amplify the joint load. The knee acts as a dynamic hinge, framed by powerful lever arms.

Thus, losing just one kilogram translates into 4 kg less pressure with each step—that's more than 20 tons less over a day's walking!

Clinical benefits

In people with knee osteoarthritis:

• Losing 5 kg often leads to a significant reduction in pain.
• Mobility improves and cartilage is better preserved.
• The risk of developing disabling osteoarthritis decreases.

A longitudinal study even showed that losing 10% of body weight reduced mechanical load and markers of synovial inflammation. 

Why Losing Just 1 kg Protects Your Knees 

Losing just 1 kg of body weight reduces the load on the knee by about 4 kg with every step (since walking generates 2.5–2.8 times body weight). The benefit is even greater when going downstairs, where the load reaches about 3.1 times body weight, and when running, where it rises to 3.6 times, making each kilogram lost particularly protective for the knee joint.  

In practice

Even a small amount of weight loss can transform your joint comfort:

• Adjust your diet, even slightly.
• Walk regularly, at a gentle and steady pace.
• Work on your posture and balance to distribute the load.

Each step then becomes a step of relief.

Learn more about Xelflex for joint health!

Scientific sources :

Messier, S. P., Gutekunst, D. J., Davis, C., & DeVita, P. (2005). Weight loss reduces knee-joint loads in overweight and obese older adults with knee osteoarthritis. Arthritis & Rheumatism, 52(7), 2026–2032. https://doi.org/10.1002/art.21139

Kutzner, I., Heinlein, B., Graichen, F., Bender, A., Rohlmann, A., Halder, A., Beier, A., & Bergmann, G. (2010). Loading of the knee joint during activities of daily living measured in vivo in five subjects. Journal of Biomechanics, 43(11), 2164–2173. https://doi.org/10.1016/j.jbiomech.2010.03.046

Damm, P., Kutzner, I., Bergmann, G., & Rohlmann, A. (2017). Comparison of In Vivo Measured Loads in Knee, Hip and Lumbar Spine. Journal of Biomechanics, 70, 110–118. https://doi.org/10.1016/j.jbiomech.2017.05.024

Henriksen, M., Lund, H., Christensen, R., Jespersen, A., Dreyer, L., Bennett, M., & Danneskiold-Samsøe, B. (2013). Weight loss reduces knee joint compressive forces during walking in obese adults with knee osteoarthritis. Arthritis Care & Research, 65(8), 1297–1304. https://doi.org/10.1002/acr.21987

Andriacchi, T. P., & Mündermann, A. (2006). The role of ambulatory mechanics in the initiation and progression of knee osteoarthritis. Current Opinion in Rheumatology, 18(5), 514–518. https://doi.org/10.1097/01.bor.0000240365.16842.4e

Van Ginckel, A., Baelde, N., Almqvist, K. F., Roosen, P., & Witvrouw, E. (2023). Immediate effects of various load-bearing activities on human knee cartilage thickness and volume: A systematic review. Sports Medicine – Open, 9(1), 58. https://doi.org/10.1186/s40798-023-00602-7