To improve bone strength, exercise should be dynamic, induce a high strain on the bone, and be applied rapidly in multiple directions. One way to achieve this is through progressive, high-load resistance training.[1] For the best effects, it’s important to utilize a heavy load (80%–85% of your maximal strength), perform training at least twice per week, and involve major muscle groups. High-impact, high-load exercises, such as jumping, bounding, skipping, drop jumps, and (to some extent) running, are also effective for stimulating bone. Incorporating these exercises 4–7 times per week at a dose of 10–50 “impacts” per day appears to be optimal.[2] Combining high-impact exercise with vitamin D and calcium or progressive resistance training can lead to further improvements in bone health.
Walking is often recommended as a way to maintain bone health. However, some meta-analyses suggest that walking has minimal to no effects on BMD, likely because the impact isn’t high enough.[3][4] In addition, prolonged endurance exercises like swimming, and cycling — while beneficial for cardiovascular health — provide very little osteogenic (bone-forming) activity.[5]