Rodeo may be another exercise that increases longitudinal bone growth

Bareback riding is horseback riding without a saddle.

As seen in the picture below bareback rodeo riding involves asymmetrical loading on one arm and it involves torsional+vibrational loading at the arm.

There is anecdotal and some study evidence that exercises that involve torsional+vibration loading such as tennis and arm wrestling can increase longitudinal bone growth even past epipihyseal fusion. Since rodeo has vibration + torsional loads the question is can it increase longitudinal bone growth as well? In short: the study below suggests that rodeo riding can increase bone size but longitudinal bone length was not measured. The difference in bone size is very large though so it looks to be an effective stimulus. I did send an email to the author of the study though.

Bony hypertrophy of the forearm in bareback rodeo athletes

“Activities that require increased load bearing are known to cause bony hypertrophy. This phenomenon has been documented in the dominant arm of athletes in sports requiring significant utilization of a single limb. The literature addressing this effect in rodeo athletes, however, is minimal. Studies evaluating rodeo athletes are primarily focused on acute injury management rather than chronic symptoms resulting from changes in bone and soft tissue. We designed a study to evaluate bony hypertrophy in athletes without acute injury.

Rodeo bareback riders presented with frequent pain in their grip arm, no radiographic evidence of injury, and clinical signs of peripheral nerve compression. Anteroposterior and lateral X-rays taken for initial evaluation in 17 bareback rodeo athletes were retrospectively reviewed. The diameter of bilateral ulnas was measured at its longitudinal midpoint. Ratio of Ulnar Diameters (grip arm/free arm) and Percentage Diameter Difference were calculated. An independent samples t-test was used to assess differences in diameters of grip and non-grip arms.

The mean ulnar diameter was 18.4 ± 3.5 in the grip arm and 16.6 ± 3.5 in the non-grip arm {this is a pretty big difference}. The mean ratio of grip to free arm ulnar diameter was 1.42 ± 0.21 (range = 1.05–1.92). The mean diameter percent difference measured 42.3% (range = 4.7%–92.0%), and the grip arm was observed to have a greater ulnar diameter compared to the non-grip arm.

There are significant anatomic differences in the grip arm of bareback rodeo athletes compared to the contralateral arm. In cases of persistent pain in the grip arm and no evidence of acute injury, these differences may be relevant to pain symptoms and should be considered as part of the assessment and treatment algorithm.”

This paper cites the paper “Chronic Hypertrophy of the Ulna in the
Professional Rodeo Cowboy”. Here is an image of that paper

The left ulna looks much wider at the epiphysis. Possibly longer.

Going back to the paper. Here’s an x-ray from the paper not the difference in bone width

Here’s an image from the paper comparing the two arms:
Left arm looks longer but we’d have to additional studies to see.

“In this study, we show that bony hypertrophy in the ulna of the grip arm of bareback rodeo riders was 42.3% greater on average when compared to the non-grip arm, which is nearly a 10-fold greater difference (between right and left) in forearm bone thickness than a previous study on tennis athletes.”<-so rodeo training may be more effective than tennis. We’d have to think about this when designing bone lengthening exercise protocols.

“This study is limited by the inclusion of only symptomatic patients. We were unable to account for previous injuries that may have influenced the bone composition of either arm. Furthermore, we are unaware if the athletes participated in other activities requiring increased stress to the grip arm. This study did not include athletes from other sports (e.g. tennis, baseball, or hockey) for direct comparison of the degree of hypertrophy seen in rodeo versus other sports.”<-So there’s selection bias and they can’t control for whether only rodeo was responsible for the effects. The athletes could have done other training that contributed.

Rodeo is an expensive sport so it’s not really something that we can self-test effectively and it’s hard to control the stimulus as it’s really based on what the bull is doing. But bull riding can provide additional evidence that torsional/vibrational loading can increase longitudinal bone growth. In this study, the grip arm does look longer so that is anecdotal evidence but that could be an illusion. This is definitely worth diving into further,