Ulnar and tibial bending stiffness as an index of bone strength in synchronized swimmers and gymnasts

Abstract

The purpose of this study is to compare a mechanical property of bone in world-class female athletes with different loading histories. Bone bending stiffness or EI (E is the modulus of elasticity and I, the moment of inertia) was measured noninvasively with the mechanical response tissue analyzer, that analyzes the response of bone to a vibratory stimulus. We evaluated the ulna, ulnar width, wrist density and tibia in 13 synchronized swimmers (SYN), eight gymnasts (GYM) and 16 untrained women (UNT) of similar age. Muscle strength in the flexors and extensors at elbows and knees was measured in the athletes. SYN were taller than GYM or UNT (168 +/- 0.7 vs. 152 +/- 1.1 or 157 +/- 1.2 cm, P < 0.01). Ulnar EI, Nm(2), was similar in SYN and GYM (41 +/- 5.4 vs. 42 +/- 4.2, NS) and 50% higher than in UNT (27 +/- 2.1, P < 0.05). Ulnar EI, Nm(2) was related to ulnar width (r = 0.497, P < 0.002, n = 37) but not to wrist density. Tibial EI, Nm(2), in SYN and GYM (270 +/- 42 vs. 285 +/- 49, NS) was similar and more than twice as high as in UNT (119 +/- 6; p < 0.05). Knee flexor strength measured at 60 degrees s(-1) and elbow extensor strength at 200 degrees s(-1) correlated with tibial EI (r = 0.44 and 0.41, P < 0.05). In spite of different loading histories, the tibiae and ulnas of world-class athletes showed similar high values for bending stiffness that exceeded values in untrained women. EI in the ulna could be related to bone width and in the tibia, to muscle strength.

Nutrition for Synchronized Swimming: A Review

“…It is also important to note that these synchronized swimmers were eumenorrheic, which may represent a best-case scenario for bone stiffness in the sport. In the same study, bone-mineral density measured in the wrist was lower in the synchronized swimmers than either the gymnasts or untrained controls, which may point to a higher risk of osteoporosis (Liang et al, 2005). The lower bone-mineral density relative to gymnasts is likely related to the nature of the training being weight supported rather than load bearing.…”

“…Overall it is a high-volume and high-intensity training program (Mountjoy, 2009), with the exception of periods devoted to choreography when much time may Scholarly reviewS be spent in the pool but with limited energy expenditure (Price & Carlsen, personal communication). Liang, Arnaud, Steele, Hatch, and Moreno (2005) found that the U.S. Olympic team trained 1,690 hr/ year, compared with around 1,000 for similar standard gymnasts. Unfortunately, they did not specify the gymnastics discipline.…”

“…Ferrand et al (2007) found that 30.3% of synchronized swimmers reported menstrual dysfunction, but most of the rest of the study group (63.6%) were taking the oral contraceptive pill so the true incidence is unknown. Liang et al (2005) used bone stiffness in the tibia and ulna as an index of bone strength in Olympiclevel synchronized swimmers, gymnasts of national or Olympic standard, and untrained age-matched controls. Both gymnasts and synchronized swimmers had bone stiffness nearly twice that of the control group.…”

Non-elite gymnastics participation is associated with greater bone strength, muscle size, and function in pre- and early pubertal girls

“…Elite gymnastics is associated with marked improvements in bone density [1] and bone strength [2,3] that may be retained at least partly later in life [1,4,5]. The skeletal gains tend to be larger in the upper body [2] due to the unique pattern of loading induced by gymnastic maneuvers on the upper limbs, including weight-bearing and large muscular forces.…”

Nutritional Recommendations for Synchronized Swimming

“…The prevalence of osteopenia in athletes is estimated at between 22 and 50% and that of osteoporosis at 13% (Khan et al, 2002). Studies done by Roby et al (1988) and Liang et al (2005) demonstrated lower BMD in the wrists of synchronized swimmers compared with gymnasts and untrained control subjects. Similar results were found for lower limb and lumbar measurements (Tanaka et al, 2006).…”