The Relationships Between Skeletal Muscle Index and Bone Variables in a Group of Young Adults

International audienceThe purpose of this study was to investigate the relationships between skeletal muscle index (SMI) and bone variables in a group of young adults. Three hundred and thirty-five young adults (129 men and 206 women) whose ages ranged from 18 to 35 yr voluntarily participated in this study. Weight and height were measured, and body mass index (BMI) was calculated. Body composition, bone mineral content (BMC), bone mineral density (BMD), geometric indices of hip bone strength and trabecular bone score (TBS) were determined for each individual by Dual-energy X-ray absorptiometry (DXA). Appendicular skeletal mass (ASM, in kg) was calculated by summing the muscle masses of the 4 limbs, assuming that all nonfat and nonebone mass is skeletal muscle. Skeletal muscle index (SMI) was defined as ASM/height². In young men, SMI was positively correlated to WB BMC (r = 0.63; p < 0.001), WB BMD (r = 0.53; p < 0.001), L1-L4 BMC (r = 0.33; p < 0.001), L1-L4 BMD (r = 0.30; p < 0.001), L1-L4 TBS (r = 0.26; p < 0.01), TH BMC (r = 0.61; p < 0.001), TH BMD (r = 0.46; p < 0.001), FN BMC (r = 0.51; p < 0.001), FN BMD (r = 0.46; p < 0.001), FN cross-sectional area (CSA) (r = 0.56; p < 0.001), FN cross-sectional moment of inertia (CSMI) (r = 0.52; p < 0.001) and FN section modulus (Z) (r = 0.54; p < 0.001) but negatively correlated to FN strength index (SI) (r = -0.24; p < 0.01). In young women, SMI was positively correlated to WB BMC (r = 0.61; p < 0.001), WB BMD (r = 0.60; p < 0.001), L1-L4 BMC (r = 0.35; p < 0.001), L1-L4 BMD (r = 0.33; p < 0.001), L1-L4 TBS (r = 0.29; p < 0.001), TH BMC (r = 0.61; p < 0.001), TH BMD (r = 0.53; p < 0.001), FN BMC (r = 0.45; p < 0.001), FN BMD (r = 0.49; p < 0.001), FN CSA (r = 0.60; p < 0.001), FN CSMI (r = 0.52; p < 0.001), and FN Z (r = 0.40; p < 0.001) but negatively correlated to FN SI (r = -0.20; p < 0.01). The current study suggests that SMI is a positive determinant of bone mineral density and geometric indices of hip bone strength in young adults

Relations entre les performances obtenues aux tests physiques anaérobies et la densité minérale osseuse chez l’adulte jeune

The main aim of this thesis was to explore the relationships between physical performances obtained in anaerobic physical tests and bone mineral density in young adults. To do so, three preliminary studies and two principal studies were conducted. The first preliminary study showed that maximal oxygen consumption (L/min) is an important determinant of BMD in young adults. The second preliminary study demonstrated that being active (engaging in more than 150 minutes of physical activity per week) is associated with greater composite indices of femoral neck strength (CSI, BSI and ISI) in young overweight men. The third preliminary study demonstrated in a group of overweight and obese men that physical activity level (h/week) was positively correlated to composite indices of femoral neck strength (CSI, BSI and ISI); the positive associations between physical activity and composite indices of femoral neck strength (CSI, BSI and ISI) remained significant after adjustment for body weight. The first principal study showed that maximum power of the lower limbs evaluated by the vertical jump test is positively correlated to BMD and geometric indices of hip bone strength in young adults. The second principal study demonstrated that maximum power evaluated by the force-velocity test on a cycle ergometer is a positive determinant of BMD in men but not in women. 20-meter sprint performance was positively correlated to femoral neck BMD in men. In conclusion, it seems that performances obtained in physical tests evaluating muscular power are correlated to BMD in young adults.Le but principal de cette thèse était d’explorer les relations entre les performances obtenues aux tests physiques anaérobies et la densité minérale osseuse chez l’adulte jeune. Pour ce faire, 3 études préliminaires et deux études principales ont été menées. La première étude préliminaire a démontré que la consommation maximale d’oxygène (L/min) est un déterminant important de la DMO chez les jeunes adultes. La deuxième étude préliminaire a démontré que le fait d’être actif (pratiquer plus de 150 minutes d’activité physique par semaine) est associé à une augmentation des valeurs de CSI, de BSI et d’ISI chez les jeunes hommes en surpoids. La troisième étude préliminaire a démontré chez des jeunes hommes en surpoids et obèses que le niveau d’activité physique est un déterminant positif des indices de résistance osseuse du col fémoral (CSI, BSI et ISI) ; les corrélations positives entre le niveau d’activité physique et les indices de résistance osseuse du col fémoral (CSI, BSI et ISI) ont persisté après ajustement pour le poids. La première étude principale a démontré que la puissance maximale des membres évaluée par le test de détente verticale est corrélée positivement à la DMO et aux indices géométriques de résistance osseuse de la hanche chez les jeunes adultes. La deuxième étude principale a démontré que la puissance maximale évaluée par le test de charge-vitesse sur bicyclette ergométrique est corrélée positivement à la DMO chez les hommes mais pas chez les femmes. La performance au 20 mètres sprint était corrélée à la DMO du col fémoral chez les hommes. En conclusion de cette thèse, il apparait que les performances obtenues aux tests physiques évaluant la puissance musculaire sont corrélables à la DMO chez l’adulte jeune

Relationships between physical performances obtained in anaerobic physical tests and bone mineral density in young adults

Le but principal de cette thèse était d’explorer les relations entre les performances obtenues aux tests physiques anaérobies et la densité minérale osseuse chez l’adulte jeune. Pour ce faire, 3 études préliminaires et deux études principales ont été menées. La première étude préliminaire a démontré que la consommation maximale d’oxygène (L/min) est un déterminant important de la DMO chez les jeunes adultes. La deuxième étude préliminaire a démontré que le fait d’être actif (pratiquer plus de 150 minutes d’activité physique par semaine) est associé à une augmentation des valeurs de CSI, de BSI et d’ISI chez les jeunes hommes en surpoids. La troisième étude préliminaire a démontré chez des jeunes hommes en surpoids et obèses que le niveau d’activité physique est un déterminant positif des indices de résistance osseuse du col fémoral (CSI, BSI et ISI) ; les corrélations positives entre le niveau d’activité physique et les indices de résistance osseuse du col fémoral (CSI, BSI et ISI) ont persisté après ajustement pour le poids. La première étude principale a démontré que la puissance maximale des membres évaluée par le test de détente verticale est corrélée positivement à la DMO et aux indices géométriques de résistance osseuse de la hanche chez les jeunes adultes. La deuxième étude principale a démontré que la puissance maximale évaluée par le test de charge-vitesse sur bicyclette ergométrique est corrélée positivement à la DMO chez les hommes mais pas chez les femmes. La performance au 20 mètres sprint était corrélée à la DMO du col fémoral chez les hommes. En conclusion de cette thèse, il apparait que les performances obtenues aux tests physiques évaluant la puissance musculaire sont corrélables à la DMO chez l’adulte jeune.The main aim of this thesis was to explore the relationships between physical performances obtained in anaerobic physical tests and bone mineral density in young adults. To do so, three preliminary studies and two principal studies were conducted. The first preliminary study showed that maximal oxygen consumption (L/min) is an important determinant of BMD in young adults. The second preliminary study demonstrated that being active (engaging in more than 150 minutes of physical activity per week) is associated with greater composite indices of femoral neck strength (CSI, BSI and ISI) in young overweight men. The third preliminary study demonstrated in a group of overweight and obese men that physical activity level (h/week) was positively correlated to composite indices of femoral neck strength (CSI, BSI and ISI); the positive associations between physical activity and composite indices of femoral neck strength (CSI, BSI and ISI) remained significant after adjustment for body weight. The first principal study showed that maximum power of the lower limbs evaluated by the vertical jump test is positively correlated to BMD and geometric indices of hip bone strength in young adults. The second principal study demonstrated that maximum power evaluated by the force-velocity test on a cycle ergometer is a positive determinant of BMD in men but not in women. 20-meter sprint performance was positively correlated to femoral neck BMD in men. In conclusion, it seems that performances obtained in physical tests evaluating muscular power are correlated to BMD in young adults

Relations entre les performances obtenues aux tests physiques anaérobies et la densité minérale osseuse chez l’adulte jeune

The main aim of this thesis was to explore the relationships between physical performances obtained in anaerobic physical tests and bone mineral density in young adults. To do so, three preliminary studies and two principal studies were conducted. The first preliminary study showed that maximal oxygen consumption (L/min) is an important determinant of BMD in young adults. The second preliminary study demonstrated that being active (engaging in more than 150 minutes of physical activity per week) is associated with greater composite indices of femoral neck strength (CSI, BSI and ISI) in young overweight men. The third preliminary study demonstrated in a group of overweight and obese men that physical activity level (h/week) was positively correlated to composite indices of femoral neck strength (CSI, BSI and ISI); the positive associations between physical activity and composite indices of femoral neck strength (CSI, BSI and ISI) remained significant after adjustment for body weight. The first principal study showed that maximum power of the lower limbs evaluated by the vertical jump test is positively correlated to BMD and geometric indices of hip bone strength in young adults. The second principal study demonstrated that maximum power evaluated by the force-velocity test on a cycle ergometer is a positive determinant of BMD in men but not in women. 20-meter sprint performance was positively correlated to femoral neck BMD in men. In conclusion, it seems that performances obtained in physical tests evaluating muscular power are correlated to BMD in young adults.Le but principal de cette thèse était d’explorer les relations entre les performances obtenues aux tests physiques anaérobies et la densité minérale osseuse chez l’adulte jeune. Pour ce faire, 3 études préliminaires et deux études principales ont été menées. La première étude préliminaire a démontré que la consommation maximale d’oxygène (L/min) est un déterminant important de la DMO chez les jeunes adultes. La deuxième étude préliminaire a démontré que le fait d’être actif (pratiquer plus de 150 minutes d’activité physique par semaine) est associé à une augmentation des valeurs de CSI, de BSI et d’ISI chez les jeunes hommes en surpoids. La troisième étude préliminaire a démontré chez des jeunes hommes en surpoids et obèses que le niveau d’activité physique est un déterminant positif des indices de résistance osseuse du col fémoral (CSI, BSI et ISI) ; les corrélations positives entre le niveau d’activité physique et les indices de résistance osseuse du col fémoral (CSI, BSI et ISI) ont persisté après ajustement pour le poids. La première étude principale a démontré que la puissance maximale des membres évaluée par le test de détente verticale est corrélée positivement à la DMO et aux indices géométriques de résistance osseuse de la hanche chez les jeunes adultes. La deuxième étude principale a démontré que la puissance maximale évaluée par le test de charge-vitesse sur bicyclette ergométrique est corrélée positivement à la DMO chez les hommes mais pas chez les femmes. La performance au 20 mètres sprint était corrélée à la DMO du col fémoral chez les hommes. En conclusion de cette thèse, il apparait que les performances obtenues aux tests physiques évaluant la puissance musculaire sont corrélables à la DMO chez l’adulte jeune

Muscular power and maximum oxygen consumption predict bone density in a group of middle-aged men.

The purpose of this study was to explore the relationships between several physical performance variables and bone parameters in a group of middle-aged men. 50 middle-aged men participated in this study. Body composition and bone variables were evaluated by DXA. Bone mineral density (BMD) was measured at the whole body (WB), total radius (TR), lumbar spine (L1-L4), total hip (TH) and femoral neck (FN). Geometric indices of femoral neck (FN) strength were also calculated by DXA. Handgrip strength, vertical jump, maximum power of the lower limbs (watts), maximal half-squat strength, maximal bench-press strength, sprint performance (10 m) and maximum oxygen consumption (VO max, L/min) were evaluated using validated tests. VO max (L/min), maximum power of the lower limbs, maximal half-squat strength, maximal bench-press strength, handgrip and lean mass were positively correlated to many bone parameters. Lean mass was the strongest determinant of WB BMC. VO max (L/min) was the strongest determinant of WB BMD, TH BMD and FN BMD. Maximum power was the strongest determinant of total radius BMD. The current study suggests that VO max (L/min), lean mass and maximum power of the lower limbs are the strongest determinants of bone variables in middle-aged men

Does Muscular Power Predict Bone Mineral Density in Young Adults?

International audienceThe aim of this study was to explore the relationships between maximum power and bone variables in a group of young adults. Two hundred and one young adults (53 men and 148 women) whose ages range from 18 to 35 years voluntarily participated in this study. Weight and height were measured, and body mass index was calculated. Body composition, bone mineral content (BMC) and bone mineral density (BMD) were determined for each individual by dual-energy X-ray absorptiometry. Vertical jump was evaluated using a validated field test (Sargent test). The highest vertical jump was selected. Maximum power (P max, in watts) of the lower limbs was calculated accordingly. In young men, maximum power was positively correlated to whole body (WB) BMC (r = 0.65; p < 0.001), WB BMD (r = 0.41; p < 0.01), L1-L4 BMC (r = 0.54; p < 0.001), total hip (TH) BMC (r = 0.50; p < 0.001), femoral neck (FN) BMC (r = 0.35; p < 0.01), FN cross-sectional area (CSA) (r = 0.33; p < 0.05) and FN cross-sectional moment of inertia (CSMI) (r = 0.50; p < 0.001). In young women, maximum power was positively correlated to WB BMC (r = 0.48; p < 0.001), WB BMD (r = 0.28; p < 0.001), L1-L4 BMC (r = 0.34; p < 0.001), TH BMC (r = 0.43; p < 0.001), TH BMD (r = 0.21; p < 0.01), FN BMC (r = 0.42; p < 0.001), FN BMD (r = 0.31; p < 0.001), FN CSA (r = 0.41; p < 0.001), FN CSMI (r = 0.40; p < 0.001) and FN Z (r = 0.41; p < 0.01). The current study suggests that maximum power is a positive determinant of WB BMC, WB BMD, FN CSA, and FN CSMI in young men. It also shows that maximum power is a positive determinant of WB BMC, WB BMD, TH BMD, FN BMD, FN CSA, FN CSMI, and FN Z in young women

Physical Performance Variables and Bone Parameters in a Group of Young Overweight and Obese Women

International audienceThe aim of this study was to explore the relationships between physical performance variables and bone parameters such as bone mineral density (BMD), bone mineral content, hip geometry indices, and trabecular bone score in a group of young overweight and obese adult women. Sixty-eight overweight/obese (body mass index ≥25 kg/m; 25.5-42.4 kg/m) young women whose ages range from 18 to 35 yr participated in this study. Body composition and bone outcomes were measured by dual-energy X-ray absorptiometry. Maximum oxygen consumption (VO max, in liter per minute) was determined indirectly using a progressive shuttle run test. One-repetition-maximum half-squat was directly measured. Vertical jump was measured and maximum power (P max) of the lower limbs was calculated. Lean mass was positively correlated to whole body (WB) BMD, total hip BMD, femoral neck (FN) BMD, femoral neck cross-sectional area (FN CSA) and femoral neck cross sectional moment of inertia (FN CSMI) (p < 0.05). VO max (in liter per minute) and muscle power were positively correlated to WB BMD, total hip BMD, FN BMD, FN CSA, and FN CSMI (p < 0.05). One-repetition-maximum half-squat was positively correlated with lumbar spine trabecular bone score, WB BMD, FN BMD, FN CSA and FN CSMI (p < 0.05). This study suggests that lean mass, vertical jump, VO max (liter per minute), muscle power and one-repetition-maximum half squat are positive determinants of BMD and hip geometry indices in young overweight and obese women

Influence of Physical Activity Level on Composite Indices of Femoral Neck Strength in a Group of Young Overweight Men.

International audienceThe aim of the present study was to explore the influence of physical activity level on composite indices of femoral neck strength (compression strength index [CSI], bending strength index, and impact strength index) in a group of young overweight men. To do so, we compared composite indices of femoral neck strength in active overweight men and insufficiently active overweight men. They were divided into 2 groups based on their physical activity level: 70 active overweight men (engaging in more than 150 minutes of physical activity per week; 8.7 ± 4.8 h/wk) and 26 insufficiently active overweight men (engaging in less than 150 minutes of physical activity per week; 1.2 ± 0.7 h/wk). Height (m) and weight (kg) were measured, and body mass index (kg/m) was calculated. Bone mineral density was measured by dual-energy X-ray absorptiometry at whole body, lumbar spine, total hip, and femoral neck. Body weight, lean mass, fat mass, and body mass index were not significantly different between the 2 groups. CSI, bending strength index, and impact strength index were significantly higher in active overweight men compared to insufficiently active overweight men. After adjustment for age, physical activity (h/wk) and lean mass, only CSI remained higher in active overweight men compared to insufficiently active overweight men. This study suggests that, in young overweight men, being active (engaging in more than 150 minutes of physical activity per week) is associated with greater composite indices of femoral neck strength. To our knowledge, this is the first study that finds a significant difference regarding composite indices of femoral neck strength between 2 groups of young overweight men with different levels of physical activity

The Relationships Between Skeletal Muscle Index and Bone Variables in a Group of Young Adults

International audienceThe purpose of this study was to investigate the relationships between skeletal muscle index (SMI) and bone variables in a group of young adults. Three hundred and thirty-five young adults (129 men and 206 women) whose ages ranged from 18 to 35 yr voluntarily participated in this study. Weight and height were measured, and body mass index (BMI) was calculated. Body composition, bone mineral content (BMC), bone mineral density (BMD), geometric indices of hip bone strength and trabecular bone score (TBS) were determined for each individual by Dual-energy X-ray absorptiometry (DXA). Appendicular skeletal mass (ASM, in kg) was calculated by summing the muscle masses of the 4 limbs, assuming that all nonfat and nonebone mass is skeletal muscle. Skeletal muscle index (SMI) was defined as ASM/height². In young men, SMI was positively correlated to WB BMC (r = 0.63; p < 0.001), WB BMD (r = 0.53; p < 0.001), L1-L4 BMC (r = 0.33; p < 0.001), L1-L4 BMD (r = 0.30; p < 0.001), L1-L4 TBS (r = 0.26; p < 0.01), TH BMC (r = 0.61; p < 0.001), TH BMD (r = 0.46; p < 0.001), FN BMC (r = 0.51; p < 0.001), FN BMD (r = 0.46; p < 0.001), FN cross-sectional area (CSA) (r = 0.56; p < 0.001), FN cross-sectional moment of inertia (CSMI) (r = 0.52; p < 0.001) and FN section modulus (Z) (r = 0.54; p < 0.001) but negatively correlated to FN strength index (SI) (r = -0.24; p < 0.01). In young women, SMI was positively correlated to WB BMC (r = 0.61; p < 0.001), WB BMD (r = 0.60; p < 0.001), L1-L4 BMC (r = 0.35; p < 0.001), L1-L4 BMD (r = 0.33; p < 0.001), L1-L4 TBS (r = 0.29; p < 0.001), TH BMC (r = 0.61; p < 0.001), TH BMD (r = 0.53; p < 0.001), FN BMC (r = 0.45; p < 0.001), FN BMD (r = 0.49; p < 0.001), FN CSA (r = 0.60; p < 0.001), FN CSMI (r = 0.52; p < 0.001), and FN Z (r = 0.40; p < 0.001) but negatively correlated to FN SI (r = -0.20; p < 0.01). The current study suggests that SMI is a positive determinant of bone mineral density and geometric indices of hip bone strength in young adults