Effect of physical activity as a caddie on ultrasound measurements of the Os calcis: a cross-sectional comparison

Improved Physical Health in Middle-Older Aged Golf Caddies Following 24 Weeks of High-Volume Physical Activity

BACKGROUND

The physical demands of golf caddying, including walking while carrying a golf bag, may potentially affect body composition, and markers of metabolic, cardiovascular, and musculoskeletal health. Therefore, this study examined the impact of 24 weeks of caddying on physical health in middle-older aged males.

METHODS

Eleven full-time experienced male caddies (age: 59 [8] y; caddying experience: 14 [12] y) were recruited from a local golf course. The following were assessed at preseason and after 24 weeks of caddying (March-September 2022): body composition, heart rate, blood pressure, blood lipids, and performance tests (static and dynamic balance, strength, and submaximal fitness). Physical activity (PA) levels were assessed at preseason and at the mid-point of the caddying season. Across the caddying season, participants completed a monthly average of 24.0 (3.8) rounds.

RESULTS

Following the caddying season, improvements in static balance (Δ = 13.5 s), dynamic balance (Δ = -1.8 s), and lower back absolute strength (Δ = 112.8 N), and muscle quality (Δ = 2.0 N·kg-1) were observed (all P < .05). Additionally, blood lipids, including total cholesterol (Δ = -0.6 mmol·L-1), high-density lipoprotein cholesterol (Δ = 0.1 mmol·L-1), low-density lipoprotein cholesterol (Δ = -0.6 mmol·L-1) (all P < .05), and body composition, including body mass (Δ = -2.7 kg), fat mass (Δ = -1.9 kg), fat percentage (Δ = -1.4%), fat-to-muscle ratio (Δ = -0.03), and body mass index (Δ = -0.9 kg·m-2) (all P < .05) improved. Caddying did not offer beneficial changes to cardiovascular variables or cardiorespiratory fitness (P > .05), while coronary heart disease risk score decreased (Δ = -3.3%) (P < .05). In relation to PA, light- (Δ = 145 min) and moderate-intensity (Δ = 71 min) PA, moderate to vigorous PA (Δ = 73 min), and total PA (Δ = 218 min) between preseason and the mid-point of the caddying season increased, while sedentary time (Δ = -172 min) decreased (all P < .05).

CONCLUSION

Golf caddying can provide several physical health benefits such as improvements in various markers of cardiometabolic health, lower back absolute strength, and static and dynamic balance. The physical health improvements that caddying offers is likely contributed to by increased PA volume and intensity through walking on the golf course. Therefore, caddying may represent a feasible model for increasing PA volume and intensity and achieve physical health-related benefits.

Golf and Physical Health: A Systematic Review

BACKGROUND

No previous systematic review has examined the physical health benefits of playing golf or caddying.

OBJECTIVE

To establish the influence of golf participation and physical health in golfers and caddies. More specifically, the review intended to explore the domains of cardiovascular, metabolic and musculoskeletal health, in addition to body composition.

DESIGN

Systematic review.

DATA SOURCES

Electronic literature searches were conducted using PubMed, SPORTDiscus and CINAHL databases in July 2021.

ELIGIBILITY CRITERIA

Experimental (randomised controlled trials, quasi-experiment, pre-post) and non-experimental (case-control, cross-sectional, cohort) articles relating to health and golf, written in English and published in peer-reviewed journals.

RESULTS

Of the 572 articles initially identified, 109 full-text articles were assessed for eligibility with 23 meeting the inclusion criteria. Sixteen articles were rated 'good 'and seven 'fair'. The influence of golf on physical health was mixed, although various articles displayed improvements in balance, systolic blood pressure (SBP) and diastolic blood pressure (DBP), high density lipoprotein-cholesterol (HDL-C) and the ratio of HDL to total cholesterol within golfers. Caddies observed improvements in bone mineral density (BMD), stiffness index and strength. Most of the findings indicate that playing golf or caddying does not influence body mass index (BMI); however, playing golf can positively change other body composition markers such as lean and fat mass.

CONCLUSION

This review demonstrated that golf participation may be an effective method for improving musculoskeletal and cardiovascular health, although mixed findings were observed. Moreover, limited longitudinal evidence suggests that playing golf can positively impact metabolic health and the influence on body composition may be parameter dependent. Additionally, the initial evidence suggests that caddying may improve musculoskeletal health. However, the studies included were limited by their methodological inconsistencies such as: study design, participant demographics and intervention prescription.

PROSPERO REGISTRATION

CRD42021267664.

The relationships between golf and health: a scoping review

OBJECTIVE

To assess the relationships between golf and health.

DESIGN

Scoping review.

DATA SOURCES

Published and unpublished reports of any age or language, identified by searching electronic databases, platforms, reference lists, websites and from consulting experts.

REVIEW METHODS

A 3-step search strategy identified relevant published primary and secondary studies as well as grey literature. Identified studies were screened for final inclusion. Data were extracted using a standardised tool, to form (1) a descriptive analysis and (2) a thematic summary.

RESULTS AND DISCUSSION

4944 records were identified with an initial search. 301 studies met criteria for the scoping review. Golf can provide moderate intensity physical activity and is associated with physical health benefits that include improved cardiovascular, respiratory and metabolic profiles, and improved wellness. There is limited evidence related to golf and mental health. The incidence of golfing injury is moderate, with back injuries the most frequent. Accidental head injuries are rare, but can have serious consequences.

CONCLUSIONS

Practitioners and policymakers can be encouraged to support more people to play golf, due to associated improved physical health and mental well-being, and a potential contribution to increased life expectancy. Injuries and illnesses associated with golf have been identified, and risk reduction strategies are warranted. Further research priorities include systematic reviews to further explore the cause and effect nature of the relationships described. Research characterising golf's contribution to muscular strengthening, balance and falls prevention as well as further assessing the associations and effects between golf and mental health are also indicated.

Bone ultrasound and physical activity in postmenopausal Spanish women

We studied the effects of moderate physical activity on bone mass in healthy postmenopausal women as assessed by quantitative bone ultrasound. We enrolled a total of 326 postmenopausal women (60.95 ± 8.51 years old and 13.02 ± 9.52 years since menopause) and categorized them by weekly physical activity in their leisure time (sedentary, moderate, and active). We administered a questionnaire on general health and diet and measured bone density by ultrasound on phalanges II-V in the nondominant hand. We found no significant difference in the amplitude-dependent speed of sound (Ad-SoS; p > .05) between sedentary and active women. We concluded that the changes induced by moderate physical activity on bone mass are minimal in healthy postmenopausal women.

Effects of physical activity on bone remodeling

Physical exercise is recommended to improve bone mass in growing children and decrease bone loss in elderly men and women. However, the specific mechanisms by which exercise influences bone metabolism are still not thoroughly understood. The effect of physical activity on the skeleton is generally evaluated by dual-energy x-ray absorptiometry, which measures bone mineral density. However, a relatively long period is needed to detect even a minor variation in bone mineral density with this technique, limiting its usefulness. Bone biochemical markers that reflect the cellular activities of bone formation and resorption are thus also useful tools, both to monitor the acute effects of exercise on bone remodeling and to investigate the mechanisms of exercise-induced changes in bone mass. This article describes the effects of physical activity on bone remodeling in various types of population. The comparison of sedentary individuals and athletes with many years of high-volume sports practice, for example, has clarified some of the long-term effects of exercise. Moreover, the acute variation in bone cell activities after brief exercise or a training program is here examined. The interpretation of results is difficult, however, because of the many parameters, such as age, that are involved. The various populations are therefore categorized to reflect the biological factors implicated in the modulation of bone marker response during exercise.

Association between alcohol consumption and bone strength in Korean adults: the Korean Genomic Rural Cohort Study

Previous studies have reported an inconsistent relationship between alcohol consumption and bone health. A growing body of research has shown that chronic alcoholism leads to osteopenia and increased incidence of skeletal fractures, but some studies have concluded that alcohol consumption may be associated with higher bone mineral density in elderly populations. However, most studies showing a significant relationship between alcohol consumption and bone status have been in Western countries; and subjects have usually been postmenopausal women. The purpose of the present study was to investigate the association of alcohol consumption with bone strength in Korean adults. Data were from the Korean Genomic Rural Cohort Study, which is an ongoing population-based study of adults aged 40 to 70 years from 5 regions. A total of 7713 participants (3368 men, 4345 women) were surveyed about their annual consumption of alcohol such as soju, beer, makkolli, wine, and whisky. Bone strength was measured by stiffness index using the calcaneal quantitative ultrasound method. Overall, the annual age-specific decrease rate in the stiffness index of women was 2.7 times higher than that of men (0.463% for women, 0.169% for men).After adjustment for eligible covariates, the association between alcohol consumption and risk of reduced bone strength showed a J-shaped curve for both men and women. Compared with nondrinkers, the relative risk of reduced bone strength was 0.52 (95% confidence interval, 0.33-0.83) in men who drank 4 to 5 cups of soju for an amount of 29.626 to 49.375 g of alcohol per day and 0.61 (95% confidence interval, 0.38-0.86) in men who drank 6 to 7 cups of soju for an amount of 49.376 to 69.125 g of alcohol per day. We found no significant relationship between alcohol consumption and bone strength in any other group of men. For women, results suggested that the risk of reduced bone strength was lower in the moderate-consumption group; but no significant relationship was found between alcohol consumption at any level and bone strength. Among Korean adults, alcohol consumption has a J-shaped relationship with risk of reduced bone strength.

Loading and skeletal development and maintenance

Mechanical loading is a major regulator of bone mass and geometry. The osteocytes network is considered the main sensor of loads, through the shear stress generated by strain induced fluid flow in the lacuno-canalicular system. Intracellular transduction implies several kinases and phosphorylation of the estrogen receptor. Several extra-cellular mediators, among which NO and prostaglandins are transducing the signal to the effector cells. Disuse results in osteocytes apoptosis and rapid imbalanced bone resorption, leading to severe osteoporosis. Exercising during growth increases peak bone mass, and could be beneficial with regards to osteoporosis later in life, but the gain could be lost if training is abandoned. Exercise programs in adults and seniors have barely significant effects on bone mass and geometry at least at short term. There are few data on a possible additive effect of exercise and drugs in osteoporosis treatment, but disuse could decrease drugs action. Exercise programs proposed for bone health are tedious and compliance is usually low. The most practical advice for patients is to walk a minimum of 30 to 60 minutes per day. Other exercises like swimming or cycling have less effect on bone, but could reduce fracture risk indirectly by maintaining muscle mass and force.

Trabecular and cortical bone separately assessed at radius with a new ultrasound device, in a young adult population with various physical activities

The aim was to evaluate a new ultrasound device in a young adult population and to assess its reproducibility via comparison to DXA measurements and geometrical measurements from high-resolution radiographs. Ninety-three subjects aged between 20 and 51 years were recruited and divided into four groups according to their gender and physical activity status: 22 male athletes, 19 male controls, 21 female athletes, and 31 female controls. Ultrasonic measurements were assessed by the prototype LD-100 (Oyo Electric Co., Kyoto, Japan) on the dominant distal radius. Attenuation in the radius (dB), cortical bone thickness (mm), radius thickness (mm), mass density of cancellous bone (mg/cm(3)), and elasticity (GPa) of cancellous bone were obtained. BMD was measured by DXA at the dominant distal radius. Radius images were obtained with a direct high-resolution digital X-ray device (BMA, D(3)A Medical Systems), and radius and cortical thicknesses were estimated using a specific software (ImageJ, Bethesda, USA), in an area site-matched with LD-100. There was a significant positive correlation between site-matched BMD measurement and LD-100 parameters (p<0.004), X-ray radius thickness, and LD-100 parameters except elasticity (p<0.05, r>0.32), X-ray cortical thickness and LD-100 attenuation and cortical thickness (p<0.01). A significantly higher attenuation, cortical and radius thicknesses were found in athletes compared to controls (p<0.05). The radius thickness measured on radiographs was significantly higher in athletes versus controls in both sexes, and cortical thickness was significantly higher in male athletes versus controls. These data suggest a positive influence of physical activity on bone cortical measurements. This study also confirmed the particular interest of bone assessment by ultrasound.

Association of physical exercise and calcium intake with bone mass measured by quantitative ultrasound

Background

Interventions other than medications in the management of osteoporosis are often overlooked. The purpose of this study was to investigate the association of physical activity and calcium intake with bone parameters.

Methods

We measured the heel T-score and stiffness index (SI) in 1890 pre- and postmenopausal women by quantitative ultrasound (QUS) and assessed physical activity and dietary calcium intake by questionnaire. Participants were divided according to their weekly physical activity (sedentary, moderately active, systematically active) and daily calcium consumption (greater than or less than 800 mg/day).

Results

SI values were significantly different among premenopausal groups (p = 0.016) and between sedentary and systematically active postmenopausal women (p = 0.039). QUS T-scores in systematically active premenopausal women with daily calcium intake > 800 mg/day were significantly higher than those in all other activity groups (p < 0.05) independent of calcium consumption.

Conclusions

Systematic physical activity and adequate dietary calcium intake are indicated for women as a means to maximize bone status benefits.

Associations of daily walking steps with calcaneal ultrasound parameters and a bone resorption marker in elderly Japanese women

Quantitative ultrasound (QUS) parameters of the calcaneus and bone resorption markers predict osteoporotic fractures. High levels of physical activity have positive effects on bone health. The purpose of this cross-sectional study was to investigate the effects of daily walking activity (number of steps taken), as an outcome of physical activity, on QUS parameters of the calcaneus and urinary deoxypyridinoline (DPD) in elderly Japanese women. The subjects were 113 postmenopausal women aged 60-85 years. The speed of sound (SOS), broadband ultrasound attenuation (BUA), and the stiffness index (Stiffness) of the calcaneus were measured with A-1000 (GE-Lunar, USA). Spot urine samples were collected between 09:00 and 10:00, and the levels of urinary DPD were measured. The subjects were instructed to wear a pedometer during waking hours for 7 consecutive days. In univariate analyses, steps/day significantly decreased with aging (r=-0.306, p<0.001). Steps/day showed significant positive correlations with SOS (r=0.252, p<0.01) and Stiffness (r=0.258, p<0.01). There was a significant decrease in DPD with steps/day (r=-0.262, p<0.01). These effects of walking on QUS parameters and DPD remained significant after adjustment for confounding factors by multiple regression analyses. We conclude that high levels of walking activity may be effective in both maintaining the levels of QUS parameters and reducing bone resorption, and hence preserve bone health in elderly women.

Association of reduced physical activity and quantitative ultrasound measurements: a 6-year follow-up study of adolescent girls

Sonographic parameters of the heel were recorded in order to investigate the effects of changes in physical activities among 140 healthy growing peripubertal Caucasian girls. Calcaneal quantitative ultrasound measurements (Hologic Sahara) were recorded at baseline and 2- and 6-year follow-up. Broadband ultrasound attenuation, speed of sound (SOS), and T scores were documented. Altogether, 30 girls reduced their physical activity by >50% and 29 girls by 25-50%, whereas 81 girls continued at the present level or increased it. Age and physical activity together accounted for 16.7% of the variation in calcaneal T scores at baseline and for 16.4% at 2-year follow-up, whereas physical activity alone accounted for 11.3% of the variation at 6-year follow-up. The reduction in mean T scores was significant (from 2.0 to 0.8, P < 0.001) among those having discontinued their physical activity by the 6-year measurement. The changes between three groups were statistically significantly different from each other (P = 0.003). The mean SOS values decreased 16.78 meters per second (95% CI -26.9 to -6.7) among those having discontinued their physical activity between the 2- and 6-year follow-up measurements. The SOS value sensitively reacts to changes in physical activity, and consequently, it will help assess changes in bone quality. Because of such an immediate reaction, SOS is a good-quality measure for the physical condition of bone in young people and a suitable tool for detecting changes in calcaneal bone.

Lifestyle factors affecting heel ultrasound in Greek females across different life stages

The use of quantitative ultrasound (QUS) of the bone is rapidly gaining in popularity, and QUS is widely used worldwide for the assessment of skeletal status. Although much has been learned about the influence of various factors on ultrasonic parameters in various populations, similar information at the local level is not available. This study was carried out to examine the effects of anthropometric, dietary, physical activity, reproductive, and other lifestyle factors on QUS parameters in healthy Greek women, including children (n=217), adults (n=235), and elderly (n=369) subjects. Calcaneal QUS measurements were performed with the SAHARA device, which measures broadband ultrasound attenuation (BUA) and speed of sound (SOS) through the os calcis; a composite parameter, the quantitative ultrasound index (QUI), and an estimate of heel bone mineral density (eBMD) were also derived. All QUS indices were higher in adult women than in girls or elderly women (P<0.05). The latter had a similar BUA to girls, but lower SOS, QUI, and eBMD (P<0.05). Most QUS parameters correlated positively with height, weight, body mass index (BMI), hip circumference, organized physical activity, and activity promoting bone mass, but negatively with the time devoted to sedentary activities and absolute carbohydrate intake (P<0.05). Age of menarche and years since menopause were negatively associated with QUS in the adult and elderly women, respectively (P<0.05). The latter relationship, however, was due to the confounding effect of advancing age. Overweight and obese females had significantly higher BUA and eBMD than normal-weight subjects (P<0.05), but similar SOS and QUI; this held true for all age groups. Likewise, in all ages, individuals spending more than 2 h/week on organized activities had significantly higher QUS indices than those spending less time on exercise (P<0.05). Further, postmenarchial girls had significantly higher age-adjusted BUA, SOS, QUI, and eBMD than premenarchial ones (P<0.05). Similarly, all QUS parameters were significantly higher in adult women with an early onset of menarche (<14 years old) than in those with a late onset (P<0.05), but no effects of menarche were detected among the elderly. No significant effects of calcium intake (which was generally adequate), smoking or alcohol drinking (which were generally low) on QUS indices were observed, in either age group. Available independent variables could explain approximately 16%-24% of the total variance in BUA, SOS, QUI and eBMD. The most important positive predictors of QUS were adulthood, time devoted to organized activities, and weight or BMI, while age and carbohydrate intake per se contributed negatively. In conclusion, age, body size, physical activity, and some aspects of reproductive history and diet appear to variably affect calcaneal QUS indices among otherwise healthy Greek women at different life stages.

Significance of intima-media thickness in femoral artery in the determination of calcaneus osteo-sono index but not of lumbar spine bone mass in healthy Japanese people

The aim of this cross-sectional study was to investigate whether physical activity and local arterial thickening may affect bone metabolism. To analyze the effects of physical activity and atherosclerosis on bone in healthy Japanese people, health-related quality of life (HRQL) and local arterial thickening were assessed by means of the Medical( )Outcomes Study 36-item Short Form (SF-36), and intimal-medial thickness (IMT) in common carotid artery (CA) and femoral artery (FA), respectively. Bone mineral density (BMD) in lumbar spine was measured by dual X-ray absorptiometry and the osteo-sono assessment index (OSI) of the calcaneus by ultrasound. Healthy subjects (106 male and 154 female) were recruited from those who participated in a local health check program at the Osaka City University Hospital. A significant correlation existed between lumbar spine BMD and calcaneus OSI (r=0.551, P<0.0001). Among various scores in SF-36, only physical functioning score correlated weakly but significantly in a positive manner with lumbar spine BMD (rho=0.156, P=0.0147) and calcaneus OSI (rho=0.190, P=0.0024). Lumbar spine BMD correlated negatively with FA IMT (rho=-0.191, P=0.0027) whereas calcaneus OSI with FA IMT (rho=-0.199, P=0.0014). Multiple regression analyses revealed a significant association between FA IMT and calcaneus OSI, whereas lumbar spine BMD did not correlate significantly with FA or CA IMT. When subjects were restricted to female, FA IMT, but not CA IMT, still showed tendency against independent factors negatively associated with calcaneus OSI. Furthermore, lumbar spine BMD, but not calcaneus OSI, was weakly but significantly associated with increased physical functioning score independently. In conclusion, it was suggested that physical activity may affect bone strength in lumbar spine and calcaneus and that FA IMT might be a significant determinant of bone strength in calcaneus, but not in lumbar spine, in healthy Japanese subjects.

Oestrogen receptor alpha genotype, and interactions between vitamin D receptor and transforming growth factor-beta1 genotypes are associated with quantitative calcaneal ultrasound in postmenopausal women

OBJECTIVE

Quantitative ultrasound (QUS) of bone is a new radiation-free, low-cost method that measures both bone mass and quality. We investigated associations between QUS parameters and polymorphisms of vitamin D receptor (VDR), oestrogen receptor alpha (ERalpha) and transforming growth factor-beta1 (TGF-beta1) genes in postmenopausal women residing in a community.

DESIGN

QUS and anthropometric characteristics were measured in postmenopausal women, and compared with regard to the VDR, ERalpha and TGF-beta1 genotypes.

PATIENTS

Among the 552 women who participated in the population-based Chung-Up osteoporosis prevalence study, 206 postmenopausal women, aged 60-69 years, were included.

MEASUREMENTS

Broadband ultrasound attenuation (BUA) and speed of sound (SOS) were measured at the left calcaneus using QUS measurement of bone, and a stiffness index (SI) was calculated. We determined the BsmI and FokI polymorphisms of VDR gene and the XbaI and PvuII polymorphisms of ERalpha gene using the polymerase chain reaction-restriction fragment length polymorphism method, and Tau29 --> C polymorphism of TGF-beta1 gene using an allele-specific polymerase chain reaction assay.

RESULTS

The XbaI polymorphism of ERalpha gene was significantly associated with SI (T-score) and BUA (P = 0.040 and P = 0.024, respectively). There were no significant differences in any QUS parameters among the genotypes of VDR and TGF-beta1. However, significant genetic interactions between the VDR and TGF-beta1 genotypes, were noted (P = 0.017 for SI and P = 0.028 for BUA between the BsmI and Tau29 --> C polymorphisms; P = 0.038 for SI and P = 0.035 for BUA between the FokI and T29 --> C polymorphisms). The combined genotypes between the BsmI and T29 --> C polymorphisms or between the FokI and T29 --> C polymorphisms, were significantly associated with the QUS parameters.

CONCLUSIONS

This study indicates that the XbaI polymorphism of ERalpha gene may influence the Quantitative ultrasound parameters in postmenopausal women, and suggests the need for further investigations about the interactions between the VDR and TGF-beta1 genes.

Leisure physical activity is associated with quantitative ultrasound measurements independently of bone mineral density in postmenopausal women

The purpose of this study was to assess the magnitude of the relationship between leisure physical activity and bone status as measured either by an Achilles ultrasound bone densitometer (QUS) or dual-energy X-ray absorptiometry (DXA) in postmenopausal women. We studied 1162 French Canadian postmenopausal women, aged 33-84 years (mean age 58 years), for QUS parameters [broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI)] measured at the right calcaneus, and bone mineral density (BMD) measured at the lumbar spine and femoral neck. Multivariate regression analyses revealed that leisure physical activity level was an independent predictor of the heel QUS parameters and of femoral neck BMD. No such association was observed for BMD of the lumbar spine. Heel QUS parameters (BUA, SOS, SI) and femoral neck BMD adjusted for interfering covariables showed a statistically significant difference between sedentary (less than three sessions/month) and active women (three or more sessions/week) (P < or = 0.001). Furthermore, after adjusting each heel QUS parameters for the mean lumbar spine BMD value, the association observed between leisure physical activity and QUS remained significant. These results suggest that regular leisure physical activity could influence QUS parameters, independently of BMD, and that quantitative ultrasound could be a suitable outcome measure in exercise studies in postmenopausal women.

Speed of sound measurements of the third metacarpal bone in young exercising thoroughbred racehorses

The purpose of this longitudinal in-field study was to evaluate the influence of exercise, age, and gender on superficial cortical bone of the third metacarpal bone (MC III) in young Thoroughbreds by measuring speed of sound (SOS) values with an axial transmission technique (Omnisense, Sunlight Ltd, Israel). Both MC III of 75 racehorses, 2 to 4 years old, were monitored with SOS measurements in 5- to 7-week intervals during a 9- month physical exercise period. Medical data and training programs (slow gallop, canter, and high-speed work) of each horse were recorded. SOS measurements began before 2-year-old horses started high-speed training. SOS values of the dorsal aspect of MC III were significantly lower in comparison with values obtained at the lateral and the medial aspect of MC III, and SOS values were inversely correlated with measurement cycles. Significant limb-associated differences in dorsal MC III SOS values were observed at measurement cycles 2, 3, and 4. SOS values obtained at the lateral and medial aspect of MC III increased with age. SOS values obtained at the dorsal aspect of MC III, decreased with age. Mares had significantly higher SOS values at the dorsal aspect of MC III, when compared with corresponding values in stallions. In 2-year-old Thoroughbreds SOS values of the dorsal MC III were significantly different between cycles 1 and 2, between cycles 3 and 4, and between cycles 4 and 5. Three-year-old horses showed significant differences between SOS values of the dorsal MC III obtained at cycles 3 and 4. Training intensities did not significantly influence SOS values. The results indicate that young exercising Thoroughbred racehorses have age-, gender-, and measurement-cycle-dependent variations in SOS values of MC III, which probably reflect adaptive variations in superficial cortical bone properties of MC III.

Effect of daily walking steps on ultrasound parameters of the calcaneus in elderly Japanese women

In this cross-sectional study, we investigated the effect of daily walking steps on ultrasound parameters of the calcaneus in elderly Japanese women. The subjects were 143 community-dwelling elderly women aged 61-87 years (mean age 71.4+/-5.5 years). The speed of sound (SOS), broadband ultrasound attenuation (BUA) and the stiffness index (Stiffness) of the calcaneus were measured. Walking steps were recorded using a pedometer for 7 consecutive days as an outcome measure of physical activity. In univariate analyses, steps/day significantly decreased with aging. SOS, BUA and Stiffness showed negative correlations with age and positive correlations with weight. Linear relationships were not seen between any of the ultrasound parameters and daily walking steps. Then, the ultrasound parameters were adjusted for age and/or weight using multiple regression models, and the relationships between the adjusted ultrasound measurements and walking steps were examined using quadratic regression models. Walking activity up to approximately 12,000 steps/day was positively associated with the adjusted ultrasound measurements, above which additional walking steps had no positive effect. We conclude that daily walking steps may be suitable for evaluating the relationship between ultrasound parameters and physical activity in elderly women, but further research is needed to confirm the effect of daily walking steps on the rate of bone loss.

Community-based survey of low quantitative ultrasound values of calcaneus in Taiwan

This study investigated prevalence and associated-factors of low quantitative ultrasound (QUS) values by screening calcaneal QUS parameters--broadband ultrasound attenuation (BUA) and speed of sound (SOS)--in population samples of three different Taiwanese communities. The study included 6,322 subjects (2,631 male and 3,691 female), aged 31 yr old or more in Shih-Pai (a metropolitan area in northern Taiwan),Yu-Chi (a mountain area in central Taiwan), and A-Lein (a seaside area in southern Taiwan). The overall response rate was 50.2%. The correlation between BUA and SOS was 0.684, p<0.001. From those who responded, we selected 403 subjects aged 31-40 yr as the reference (the young group), and their BUA was 65.34+/-7.91 dB/MHz. The t-score was calculated from the BUA data of our reference group. The percentile of -2.5<t-score<-1.0 and t-score< or =-2.5 in male subjects was 21.4 and 2.9%, respectively, and in female subjects 24.2 and 14.1%, respectively. The BUA of urban area subjects was higher than that of rural area subjects in almost all age-strata, and overweight was noted to be a protective factor. The effect of age-adjusted odds ratio (AOR) on low QUS values in females was significantly increased every 10 yr from 1.55, 5.13, 13.81, 34.29, to 38.14. This survey showed that age-related decreases in calcaneal ultrasonometry, indicating prevalence of low QUS values, were more obvious in female than male subjects. Overall 38.3% of the female Taiwanese had low QUS values, and this is approximately equivalent to the lifetime risk of fracture at the hip, spine, or distal forearm in Caucasian women. The specific t-score designation, as World Health Organization (WHO) criteria, applied to calcaneal QUS are reasonable when the reference group is selected from the same population.

Relationships among physical activity, metacarpal bone mass, and bone resorption marker in 70 healthy adult males

The purpose of the present study was to investigate the relationships among physical activity, metacarpal bone mineral density (BMD), and bone resorption marker in healthy active adult men. Seventy healthy men (mean age, 68.4 years, range, 48-85 years) were recruited. The metacarpal BMD of the nondominant hand was measured by computed X-ray densitometry, and the levels of urinary cross-linked N-telopeptides of type I collagen (NTx), as a marker of bone resorption, were measured with an enzyme-linked immunosorbent assay. The relationships among BMD, urinary NTx levels, and activities in leisure time and at work were examined. BMD was 2.77 +/-0.48 (mean+/- SD; range, 1.54-3.60) mmAl, and NTx levels were 44.9 +/-21.0 (range, 11.7 - 91.0) nmol BCE/mmol creatinine. Single regression analysis showed that BMD was significantly correlated with NTx levels and activity at work (r = - 0.331 and P < 0.01; r = 0.468 and P < 0.05, respectively), while NTx levels were significantly correlated with activities in leisure time and at work (r = -0.250 and P < 0.01; r = -0.325 and P < 0.01, respectively). NTx levels were decreased and BMD were increased with higher activity at work. The present study shows that increased physical activity as a result of hard work may have the potential to decrease bone resorption and increase BMD in healthy adult men.

Effect of surgical treatment on physical activity and bone resorption in patients with neurogenic intermittent claudication

The effect of surgical treatment on physical activity and bone resorption was examined in patients with neurogenic intermittent claudication. Nineteen patients, 50-77 years of age, with neurogenic intermittent claudication (mean, 162 m; range, 20-400 m) caused by degenerative lumbar disease were included in the study. Decompressive laminectomy alone was performed for 7 patients with lumbar spinal stenosis (LSS) and 5 patients with degenerative lumbar spondylolisthesis (DLSL), and decompressive laminectomy, with a Graf stabilization system, was performed for 7 patients with DLSL associated with flexion instability. Clinical symptoms and levels of urinary cross-linked N-telopeptides of type I collagen (NTx) were assessed before and 12 months after surgery. Subjective symptoms, including low back pain, leg pain and/or tingling, and gait disturbance, as well as restriction of activities of daily living were significantly alleviated by the surgical treatment, resulting in an increase in physical activity. Urinary NTx levels were significantly decreased by the surgical treatment, from 63.1 +/- 16.9 (mean +/- SD) nmol BCE/mmol Cr to 52.1 +/-11.2 nmol BCE/mmol Cr (P < 0.05). These findings suggest that surgical treatment appears to alleviate the clinical symptoms and increase physical activity in patients with LSS or DLSL, potentially resulting in the suppression of bone resorption. Surgical treatment may contribute to the prevention of physical inactivity-induced osteoporosis in elderly patients with neurogenic intermittent claudication caused by degenerative lumbar disease.

Mechanical strain, induced noninvasively in the high-frequency domain, is anabolic to cancellous bone, but not cortical bone

Departing from the premise that it is the large-amplitude signals inherent to intense functional activity that define bone morphology, we propose that it is the far lower magnitude, high-frequency mechanical signals that continually barrage the skeleton during longer term activities such as standing, which regulate skeletal architecture. To examine this hypothesis, we proposed that brief exposure to slight elevations in these endogenous mechanical signals would suffice to increase bone mass in those bones subject to the stimulus. This was tested by exposing the hind limbs of adult female sheep (n = 9) to 20 min/day of low-level (0.3g), high-frequency (30 Hz) mechanical signals, sufficient to induce a peak of approximately 5 microstrain (micro epsilon) in the tibia. Following euthanasia, peripheral quantitative computed tomography (pQCT) was used to segregate the cortical shell from the trabecular envelope of the proximal femur, revealing a 34.2% increase in bone density in the experimental animals as compared with controls (p = 0.01). Histomorphometric examination of the femur supported these density measurements, with bone volume per total volume increasing by 32% (p = 0.04). This density increase was achieved by two separate strategies: trabecular spacing decreased by 36.1% (p = 0.02), whereas trabecular number increased by 45.6% (p = 0.01), indicating the formation of cancellous bone de novo. There were no significant differences in the radii of animals subject to the stimulus, indicating that the adaptive response was local rather than systemic. The anabolic potential of the signal was evident only in trabecular bone, and there were no differences, as measured by any assay, in the cortical bone. These data suggest that subtle mechanical signals generated during predominant activities such as posture may be potent determinants of skeletal morphology. Given that these strain levels are three orders of magnitude below strains that can damage bone tissue, we believe that a noninvasive stimulus based on this sensitivity has potential for treating skeletal complications such as osteoporosis.

Age-associated changes in bone ultrasonometry of the os calcis

This cross-sectional study updated age changes for ultrasonometry (QUS) of the os calcis in a large sample of healthy German women. The speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness index (SI) of the os calcaneus were measured in 5148 women (mean age 55.2 +/- 10.6 yr) using the Achilles ultrasonometer (GE/Lunar). There was an overall decline of 16% for BUA, 4% for SOS, and 32% for SI between late adolescence and old age. In premenopausal women, BUA decreased only slightly (-2%), whereas postmenopausal women showed a significantly increased decline (-12%). In contrast, SOS continuously decreased from the age of 15; there was a decline of 2% from adolescence to menopause. The SI of premenopausal women decreased only by 9%, but the postmenopausal decline of almost 21% was significantly greater. In accordance to our previous report, the age regression for SI in the larger sample differed from the earlier sample, indicating an increased bone loss with aging after the menopause. The SI values in premenopausal German women were comparable to those for British and American women 20-50 yr of age. After age 50, the SI of German women was significantly 3-7% higher in comparison to the British and American reference population.

Effect of administration of lipoprostaglandin E(1) on physical activity and bone resorption in patients with neurogenic intermittent claudication

The effect of the systemic administration of prostaglandin (PG) E(1) on physical activity and bone resorption was examined in patients with intermittent claudication (gait disturbance). Twenty male patients (age, 67.2 +/- 7.8 years; mean +/- SD) with neurogenic intermittent claudication caused by lumbar spinal canal stenosis were included in the study. Lipo-PG E(1) was administered intravenously, at a daily dose of 10 microg, on 3 days a week, for 6 months in all patients. Clinical symptoms, levels of urinary cross-linked N-telopeptides of type I collagen (NTx), and metacarpal cortical bone mineral density (BMD) were assessed before and just after the 6 months of treatment. Subjective symptoms, including leg pain and/or tingling and gait disturbance, and restrictions of the activities of daily living were significantly improved. However, no significant changes were observed in either urinary NTx levels or metacarpal cortical BMD. These findings suggest that the systemic administration of PG E(1) appears to improve subjective symptoms and activities of daily living in elderly male patients with neurogenic intermittent claudication, but does not affect either bone resorption or metacarpal cortical BMD. Short-term systemic administration of PG E(1) and increased physical activity in elderly male patients with gait disturbance caused by lumbar spinal canal stenosis may not affect bone resorption.

Quantitative ultrasound in postmenopausal osteoporosis

Ultrasound has been proposed as a low-cost, radiation-free method for osteoporosis assessment in postmenopausal women. Large prospective studies have shown that ultrasound parameters can be used for fracture risk estimate in this population, providing that adequate quality control is performed. The places of both ultrasound and the current gold standard method for bone assessment, dual energy x-ray absorptiometry, are still to be determined. Further studies are needed on the diagnosis of osteoporosis using ultrasound, because current diagnostic thresholds, designed by the World Health Organization, do not apply to this-new technology. Monitoring of skeletal changes and treatment effects by ultrasound cannot be recommended.

The influence of physical activity on the response of bone mineral density to 5 years tibolone

OBJECTIVES

Menopausal hormone replacement therapy (HRT) maintains bone mineral density (BMD) and reduces risk of fracture in postmenopausal women. It has been suggested that sex steroids and loading may have synergistic effects on bone. We therefore investigated whether habitual physical activity influences the response of BMD to tibolone in postmenopausal women.

METHODS

The subjects were 42 postmenopausal women aged mean (SE) 65.8+/-6.2 year who had taken tibolone for prevention/ treatment of osteoporosis over 5 years. Bone mineral density was measured annually by dual X-ray absorptiometry and physical activity was assessed using accelerometers after 5 years therapy.

RESULTS

Twenty-six women were classified as having low physical activity (LPA; <15 min day(-1)) and sixteen as high physical activity (HPA; >15 min day(-1)). Spine BMD did not differ significantly between groups at baseline and increased significantly by 2 years of treatment with further increase to 5 years. The magnitude of increase did not differ between groups. Hip BMD at baseline was 7.3% higher in HPA women (P=0.07). Hip BMD increased over 2 years tibolone treatment in LPA women (+5.6%, P<0.01) whilst no significant change occurred in the HPA group (-0.5%). This difference in response between groups was statistically significant (P=0.002) and persisted after adjustment for age and body mass (P=0.002). Hip BMD was maintained in both groups over the subsequent 3 years of treatment.

CONCLUSIONS

Spine BMD increased significantly in response to tibolone irrespective of physical activity participation. The more physically active women had higher hip BMD at baseline but the response to tibolone was greater in the less physically active women. The difference in response between groups may be due to physically active women having lower resorption at the hip and hence reduced response to anti-resorptive effects of HRT.

Prevalence and risk factors of low quantitative ultrasound values of calcaneus in Korean elderly women

Quantitative ultrasound (QUS) of bone is a new radiation-free, low-cost method that measures both bone mass and bone quality. This study was performed to establish the normative data of QUS for Korean women and to determine the prevalence and risk factors of low quantitative ultrasound values in a Korean elderly population. We studied 238 healthy women aged 20-29 years working at a hospital, and 552 women over 50 years of age living in six villages of Chung-Up district, a rural area of South Korea, using QUS measurement of bone. Broadband ultrasound attenuation and speed of sound were measured at the calcaneus, and an index combining these factors (stiffness index) was calculated. T-score was calculated from the data of young normal subjects. Of the 552 elderly women, 34.2% had T-scores between -1.0 and -2.5, and 11.8% had T-scores below -2.5. The prevalence of low quantitative ultrasound values increased with older age, longer duration following menopause, lower body mass index, younger age at menopause and smoking. In multiple logistic regression analysis, age (odds ratio = 1.40 per 5 years, P < 0.05), duration following menopause (odds ratio = 1.35 per 5 years, P < 0.05) and body mass index (odds ratio = 0.78 per quartile, P < 0.05) were independently associated with low quantitative ultrasound values. These results suggested that quantitative ultrasound measurement of the calcaneus could be a useful tool for epidemiological surveys of bone mass.

The roles of exercise and fall risk reduction in the prevention of osteoporosis

In summary, the optimal model for the prevention of osteoporotic fractures includes maximization and maintenance of bone strength and minimization of trauma. Numerous determinants of each have been identified, but further work to develop preventative strategies based on these determinants remains to be undertaken. Physical activity is a determinant of peak BMD. There also is evidence that activity during growth modulates the external geometry and trabecular architecture, potentially enhancing skeletal strength, while during the adult years activity may reduce age-related bone loss. The magnitude of the effect of a 7% to 8% increase in peak BMD, if maintained through the adult years, could translate to a 1.5-fold reduction in fracture risk. Moreover, in the older population, appropriate forms of exercise could reduce the risk of falling and, thus, further reduce fracture risk. These data must be considered as preliminary in view of the paucity of long-term fracture outcome data from randomized clinical trials. However, current information suggests that the optimal form of exercise to achieve these objectives may vary through life. Vigorous physical activity (including weight-bearing, resistance, and impact components) during childhood may maximize peak BMD. This type of activity seems optimal through the young adult years, but as inevitable age-related degeneration occurs, activity modification to limit the impact component of exercise may become necessary. In the elderly, progressive strength training has been demonstrated to be a safe and effective form of exercise that reduces risk factors for falling and may also enhance BMD. In the frail elderly, activity to improve balance and confidence also may be valuable. Group activities such as Tai Chi may be cost-effective. Precise prescriptions must await the outcome of well-designed, controlled longitudinal studies that include fracture as an outcome. However, increased physical activity seems to be a sensible component of strategies to reduce osteoporotic fracture.

Influence of handedness on calcaneal ultrasound: implications for assessment of osteoporosis and study design

Calcaneal ultrasound has been increasingly studied for its potential in the assessment of osteoporotic fracture risk. The accuracy of such an assessment is, in part, dependent on the reproducibility of the measurement. This study examines the impact of handedness on ultrasound measurements [broadband ultrasound attenuation (BUA) and velocity of sound (VOS)] in the calcaneus. Two hundred and sixty-four subjects (57 men and 297 women) aged 51.1 +/- 13.6 years (mean +/- SD) were studied. For each subject, calcaneal ultrasound measurements were performed on both heels with a McCue CUBA ultrasound densitometer. Right-handed dominance (94.7%) was determined by structured interview. In men, BUA measurements were significantly higher on the dominant side: mean difference 4.1 +/- 1.5 dB/MHz (mean +/- SD; p = 0.009), equivalent to 4.2 +/- 1.5% and more than 4 times the average rate of annual change in BUA. The difference between sides was greater in young (< 50 years) than old men (> 50 years). Among the women, the difference was not statistically significant (0.7 +/- 0.9 dB/MHz; p = 0.4); however, it was significant in younger women (20-30 years) (99 +/- 4 vs 90 +/- 4 dB/MHz, p = 0.01). By contrast VOS did not differ between sides in either men or women irrespective of age. Within-subject standard deviation of BUA was 9.8 dB/MHz for men and 8.6 dB/ MHz for women and the component due to right and left difference was 8.4 dB/MHz for men and 6.9 dB/MHz for women. This variability of BUA between right and left heels could increase the false-positive rate by up to 28% for a cut-off of 2 SD below the mean. These data indicate that variation between left and right heel measurements of BUA is higher than that of random error measurements, particularly in men and younger, presumably more physically active subjects. Although VOS measurements were not side dependent, in the smaller number of studies examining VOS and fracture risk, VOS appears to have a weaker predictive power than BUA. Clinical and epidemiological studies involving calcaneal BUA measurements should standardize the side measured to either the dominant or non-dominant heel, to reduce within-subject variation and increase their power.

The epidemiology of quantitative ultrasound: a review of the relationships with bone mass, osteoporosis and fracture risk

Quantitative ultrasound (QUS) is a simple, inexpensive and non-invasive measure of bone which has been used in research settings for the prediction of osteoporosis. This review summarizes the current status of the epidemiology of QUS analysis, including its relationship with bone mineral density (BMD), risk of osteoporotic fracture and risk factors for osteoporosis. Although only moderately correlated with BMD, QUS appears to be as strong a predictor of osteoporotic fracture as BMD and may predict fracture independent of BMD. Risk factors for low QUS, including age, menopause, body composition and physical inactivity, seem to parallel those of low BMD. More longitudinal research is needed to confirm the clinical utility of QUS and more experimental and population-based studies are needed to determine whether the etiology of low QUS values is different from that of low bone mass.