Asociación entre obesidad y baja capacidad muscular y función cardiorrespiratoria, factores de riesgo cardiometabólico en niños colombianos / Association between obesity and low muscular and cardiorespiratory capacity, cardiometabolic risk factors in Colombian children

Objetivo: Examinar la asociación entre capacidad cardiorespiratoria y muscular y la presencia de obesidad y otros factores de riesgo cardiovascular y metabólico en escolares. Material y método: Estudio de corte transversal, realizado en 336 niños y niñas escolarizados en los grados 5º y 6º de colegios públicos de Bucaramanga, Colombia. Resultados: Se encontraron correlaciones inversas significativas entre índice de masa corporal (IMC) y fuerza de empuñadura ajustada por peso (-0.532) (P<0.001), salto largo (-0.248) (P<0.001) y la prueba de Yo-Yo (-0.321) (P<0.001). La fuerza de empuñadura máxima se correlacionó de forma inversa con la presión arterial sistólica (PAS) (-0.115) (p<0.05). Conclusión: La obesidad evaluada por el IMC y el porcentaje de grasa corporal se relacionan inversamente con la aptitud muscular y cardiorrespiratoria en escolares (AU)

Objective: To examine the association between cardio respiratory and muscular fitness and the presence of obesity and other cardiovascular and metabolic risk factors in school children. Material and method: Cross-sectional study, conducted in 336 school children (boys and girls) in grade 5º and 6º of public schools in the city of Bucaramanga, Colombia. Results: Significant inverse correlations were found between body mass index (BMI) and grip strength adjusted for weight (-0532) (P <0.001), long jump (-0248) (P <0.001) and Yo-Yo test (- 0.321) (P <0.001). The maximum grip strength was correlated inversely with systolic blood pressure (SBP) (-0115) (p <0.05). Conclusion: Obesity assessed by BMI and body fat percent is inversely related with muscular and cardio respiratory fitness in Colombian school children (AU)

A DXA study of muscle-bone relationships in the whole body and limbs of 2512 normal men and pre- and post-menopausal women.

A whole-body DXA study of 1450 healthy Caucasian individuals [Bone 22 (1998) 683] found that mineral mass, either crude (BMC) or statistically adjusted to fat mass (FM-adjusted BMC), correlated linearly with lean mass (LM, proportional to muscle mass). The results showed similar slopes but decreasing intercepts (ordinate values) in the order: pre-MP women > men > post-MP women > children. This supports the hypothesis that sex hormones influence the control of bone status by muscle strength in all species. Now we further study those relationships in 2512 healthy Hispanic adults (307 men, 753 pre-MP women, 1452 post-MP women), including separate determinations in their upper and lower limbs. The slopes of the BMC or FM-adjusted BMC vs. LM relationships were parallel in all the studied regions. However, region-related differences were found between the ordinates of the curves. In the whole body, the crude-BMC/LM relationships showed the same ordinate differences as previously observed. In the lower limbs, those differences were smaller in magnitude but highly significant, showing the order: pre-MP women > men = post-MP women. In the upper limbs, the decreasing ordinate order was: men > pre-MP women > post-MP women. After fat adjustment of the BMC, order in both limbs was: men > pre-MP women > post-MP women. Parallelism of the curves was maintained in all cases. LM had a larger independent influence on these results than FM, body weight, or age. The parallelism of the curves supports the idea that a common biomechanical control of bones by muscles occurs in humans. Results suggest that sex-hormone-associated differences in DXA-assessed muscle-bone proportionality in humans could vary according to the region studied. This could be related to the different weight-bearing nature of the musculoskeletal structures studied. Besides the obvious anthropometric associations, FM would exert a mechanical effect as a component of body weight, evident in the lower limbs, while muscle contractions would induce a more significant, dynamical effect in both lower and upper limbs. Muscles seem to exert a larger influence than FM, body weight, and age on BMC in the whole body and lower limbs, regardless of the gender and reproductive status of the individual. The muscle-bone relationships studied may provide a rationale for a future differential diagnosis between disuse-related and other types of osteopenia.

Bone-mass peak in multiparity and reduced risk of bone-fractures in menopause.

OBJECTIVES: Pregnancy has been proposed as a risk factor for the development of osteoporosis; however, the results are controversial. Women in Colombia are multiparous, and therefore they represent an ideal population for the investigation of the effect of parity on osteoporosis. METHODS: The study included 1855 post-menopausal Hispanic women from Barranquilla, Colombia who were referred to our osteoporosis clinic for a routine evaluation of their bone mineral status. Bone mineral density (BMD, g/cm(2)) was measured using dual energy X-ray absorptiometry. Total body, femoral and lumbar areas were scanned. RESULTS: BMD of total body, hip and legs (P<0.0001), Ward's area (P<0.002) and intertrochanteric area (P<0.003) was high in women with at least one delivery in comparison with nulliparous women. Total mineral and calcium body contents were also high in women after second delivery. A history of fractures was found in 22.9% (n=425) of the study women. The relative risk for bone-fractures was high (O.R. 0.41; P<0.000002) in nulliparous women in comparison to multiparous women. In addition, osteopenia (O.R. 2.01; P=0.008) and osteoporosis (O.R. 3.99; P=0.0004) were most often present in nulliparous women in comparison to multiparous women. CONCLUSIONS: Pregnancies in this population appear to be a protective factor against development of osteoporosis. The increase in total mineral and calcium contents was related to the number of pregnancies, suggesting the existence of a bone mass peak during pregnancy.

Hormone replacement therapy for bone protection in multiparous women: when to initiate it.

OBJECTIVE: Hormone replacement therapy is used in postmenopausal women to improve symptoms of menopause and to protect bone and the cardiovascular system. We have evaluated the effects of parity in terms of number of deliveries on bone density and fracture risk at different ages. STUDY DESIGN: We evaluated 1875 Hispanic women > or =50 years old (61.3 +/- 8.3 years), 425 with a history of nonselective fractures and 1450 without previous fractures. Body mass index was 27.3 +/- 4.3 kg/m(2). Bone mineral densities were determined for the total body in 1468 cases, the femur in 221 cases, and the lumbar spine in 189 cases. Women were classified according to lifetime number of deliveries (from 0 to > or =5), and bone mineral densities and odds ratios for fracture risk were calculated relative to the number of deliveries. RESULTS: Bone mineral densities in total body, pelvis, and legs and total calcium and total mineral contents increased (P <.001) with > or =2 deliveries among women 50 to 59 years old but not among those > or =70 years old. The prevalence of fractures was higher in nulliparous than in multiparous women at all ages. Fracture risk was lower in multiparous women at all age groups, including those > or =70 years old (odds ratio, 0.47; 95% confidence interval, 0.26-0.84; P <.006). CONCLUSION: Bone mineral density increases with the number of deliveries until the age of 69 years. Fracture prevalence and fracture risk are lower among multiparous women even at older ages. These findings suggest that hormone replacement therapy can be delayed until 65 years of age for multiparous women but should be initiated at the beginning of menopause for nulliparous women.