Increase In Body Bone Mineral Content Research Articles

Osteogenic Response After Six Months of High-Intensity, Low-Impact Exercise

PURPOSE: Lagree Fitness exercise offers high-intensity, low impact workouts that combine resistance, endurance, core, and cardio training. These classes are offered as alternatives to traditional weight bearing resistance training; however, it is unknown whether this training method has osteogenic effects on bone similar to traditional resistance training. To provide such insight, we assessed changes in bone after six months of the high-intensity training using the Lagree Fitness Megaformer in men and women. METHODS: 31 healthy participants began a 6 month, 3x per week, 25 minute group lead, Lagree Fitness training course on the Megaformer. The data from 19 women and 4 men (45.1 ± 20.9 years of age), weight (150.5 ± 41.5 lb), height (66.5 ± 6.5 in) were analyzed; eight participants did not complete the course and were excluded from data analysis. All participants completed a lumbar spine, bilateral hip, and total body scan on a GE Lunar iDXA dual-energy x-ray absorptiometer at baseline and within 10 days of completing 72 training sessions. RESULTS: There were no significant osteogenic effects on lumbar spine bone mineral density (BMD) (P=.102), femoral neck BMD (P=.519), or total hip BMD (P=.481) in this sample. There was also no significant changes in total body bone mineral content (BMC). While there were no statistically significant changes in total body BMD (P= .186), total arm BMD (P=.125) and total leg BMD (P=.111), there were apparent positive increases that may be promising and suggests the necessity for further data collection with a larger sample. There were similar positive effects on total arm BMC (P=.292) with statistically significant increases in total leg BMC (P <.035). The increase from baseline of total arm lean mass (LM) (P < .009) was significant, and increases in total body LM (P=.069) approached significance. Change in total leg LM (P=.382) was not significant. CONCLUSION: In the absence of weight bearing exercise, high-intensity exercise on the Lagree Fitness Megaformer provided significant increase in total leg BMC, and promising increases in BMC and BMD across other body regions. However, there were no significant osteogenic effects on the hips and lumbar spine typically of importance in osteopenic populations.

The effect of a high-impact jumping intervention on bone mass, bone stiffness and fitness parameters in adolescent athletes

SummaryThis study demonstrates that a 9-month jumping intervention can improve bone mass gains and physical fitness performance in adolescent males participating in non-osteogenic sports, such as swimming and cycling.PurposeTo examine the effect of a jumping intervention on bone mass, bone stiffness and fitness parameters in adolescents involved in different sports.MethodsNinety-three adolescent male swimmers (SWI), footballers (FOO) and cyclists (CYC) were randomised to intervention (INT) and sport (INT-SWI = 19, INT-FOO = 15, INT-CYC = 14) or sport only (CON-SWI = 18, CON-FOO = 15, CON-CYC = 12) groups. The 9-month jumping intervention consisted of 3 levels (12 weeks each) of 20 repetitions per set of counter movement jumps (CMJ) using adjustable weight vests (level 1 = 20 CMJ jumps/set, 0 kg, 3 sets/day, 3 times/week; level 2 = 20 CMJ jumps/set, 2 kg, 4 sets/day, 3 times/week; level 3 = 20 CMJ jumps/set, 5 kg, 4 sets/day, 4 times/week). Total body bone mineral content (BMC) at total body less head (TBLH) was measured using dual-energy X-ray absorptiometry and bone stiffness using quantitative ultrasound. Fitness was assessed using the 20-m shuttle run (20mSRT), CMJ and standing long jump (SLJ) tests.ResultsINT-SWI had significantly higher increase in BMC legs and bone stiffness compared to CON-SWI (4.2–12.7%). INT-CYC had significantly higher increase in BMC at TBLH and legs and bone stiffness compared to CON-CYC (5.0–12.3%). There were no significant differences between INT-FOO and CON-FOO in any bone outcomes (0.9–3.9%). The increase in CMJ performance was significantly higher in INT-SWI (3.1 cm) and INT-CYC (3.2 cm) compared to CON-SWI and CON-CYC groups, respectively.ConclusionsA 9-month jumping intervention can improve bone mass, bone stiffness and muscular fitness in adolescent males participating in non-osteogenic sports, such as swimming and cycling.Clinical Trial RegistrationISRCTN17982776.

Fat mass increase in 7-year-old children: More Bone Area but lower Bone Mineral density

The main aims of this study were, to evaluate what effect a change in fat mass (FM) and lean body mass (LBM) has on bone parameters over 2years' time, in 7-year-old school children and to see what effect fitness had on bone parameters in these children. A repeated-measures design study was conducted where children born in 1999 from six elementary schools in Reykjavik, Iceland were measured twice. All children attending second grade in these six schools were invited to participate. Three hundred twenty-one children were invited, 211 underwent dual-energy X-ray absorptiometry (DXA) scans at the age of seven, and 164 (78%) of the 211 had DXA scans again 2years later. Increase in both FM and LBM was associated with increased total body bone mineral content (BMC) and bone area (BA). An increase in FM was more strongly positively associated with BA while an increase in LBM was more strongly associated with an increase in BMC. An increase in FM was negatively associated with change in bone mineral density (BMD), but an increase in LBM was positively associated with change in BMD. Fitness was positively associated with bone parameters when weight, height and sex were accounted for. The present results suggest that an increase in fat mass over 2years is associated with an increase in BA and BMC, but a decrease in BMD in the whole body. An increase in LBM accrual, on the other hand, is positively associated with all bone parameters in the body. Fitness is associated with both BMC and BMD but not BA.

Total body and regional measurements of bone mineral content and bone mineral density in pigs by dual energy X-ray absorptiometry.

Dual energy X-ray absorptiometry (DXA) was used to make total body and regional measurements of bone mineral content, bone mineral density, and bone area during the growth of pigs from 3 to 138 kg. In all, 1,053 total body scans were performed on 587 live pigs. Regional measurements consisted of the front legs, trunk, and back legs. In addition, bone mineral density readings were recorded for the head, pelvis, spine, and ribs. From about 5 to 75 kg, a greater percentage of the total body bone mineral content (BMC) was located in the trunk region. However, the percentage of BMC in the front and back legs continued to increase linearly whereas the percentage of BMC in the trunk region peaked at about 25 kg and then decreased logarithmically. Allometric analysis revealed that up to about 30 kg the BMC increased more rapidly in the trunk region compared to the front or back leg regions (P > 0.05), but after 30 kg the increase in BMC was more rapid in the leg regions (P < 0.05). Overall, the rate of increase in BMC in the back legs was slightly more than in the front legs (P > 0.05). Positive allometric growth of BMC was observed when compared with the increase in bone area for the same region. By far, the highest measured level of bone mineral density (BMD) was in the head region (P < 0.05), followed in order by the front legs, spine, back legs, pelvis, and ribs. Over the entire range of growth from 3 to 138 kg, the highest relative growth coefficient for the increase in BMD occurred in the pelvic and back leg regions and the lowest was in the ribs (P < 0.05). For pigs < 30 kg, the highest growth coefficient for BMD relative to BW was in the spine (P > 0.05). The growth coefficients for BMD in the back legs and total body increased in pigs > 30 kg and those of the front legs and trunk regions decreased.