Gianni Maddalozzo | Oregon State University (original) (raw)

Papers by Gianni Maddalozzo

Alcoholism: Clinical and Experimental Research, Sep 17, 2019

Background:Estrogen signaling is essential for the sexual dimorphism of the skeleton, is required... more Background:Estrogen signaling is essential for the sexual dimorphism of the skeleton, is required for normal bone remodeling balance in adults, and may influence the skeletal response to alcohol. High levels of alcohol consumption lower bone mass in ovary-intact but not ovariectomized (ovx) rats. However, the extremely rapid rate of bone loss immediately following ovx may obscure the effects of alcohol. We therefore determined (1) whether heavy alcohol consumption (35% caloric intake) influences bone in sexually mature ovx rats with established cancellous osteopenia, and (2) whether ICI 182,780 (ICI), a potent estrogen receptor-signaling antagonist, alters the skeletal response to alcohol.Methods:Three weeks following ovx, rats were randomized into five groups: (1) baseline, (2) control+vehicle, (3) control+ICI, (4) ethanol+vehicle, or (5) ethanol+ICI and treated accordingly for four weeks. Dual energy X-ray absorptiometry, micro-computed tomography, blood measurements of markers of bone turnover, and gene expression in femur and uterus were used to evaluate response to alcohol and ICI.Results:Rats consuming alcohol had lower bone mass and increased fat mass. Bone microarchitecture of the tibia and gene expression in femur were altered; specifically, there was reduced accrual of cortical bone, net loss of cancellous bone, and differential expression of 19/84 genes related to bone turnover. Furthermore, osteocalcin, a marker of bone turnover, was lower in alcohol-fed rats. ICI had no effect on weight gain, body composition, or cortical bone. ICI reduced cancellous bone loss and serum CTX-1, a biochemical marker of bone resorption; alcohol antagonized the latter two responses. Neither alcohol nor ICI affected uterine weight or gene expression.Conclusion:Alcohol exaggerated bone loss in ovx rats in the presence or absence of estrogen receptor blockade with ICI. The negligible effect of alcohol on uterus and limited effects of ICI on bone in alcohol-fed ovx rats suggests that estrogen receptor signaling plays a limited role in the action of alcohol on bone in a rat model for chronic alcohol abuse.

Medicine and Science in Sports and Exercise, May 1, 2011

To determine if the restoration of menses in endurance-trained women, using a daily carbohydrate-... more To determine if the restoration of menses in endurance-trained women, using a daily carbohydrate-protein (CHO-PRO) supplement, is associated with improvements in EA and RMR. METHODS: Active women with ExMD (n=8; 7 amenorrheic, 1 oligomenorrheic, age=23±3y, VO2max=49±6 mL/kg/min, body fat=22±4%) participated in a 6-mo intervention and consumed 325 mL/d of CHO-PRO supplement (360 kcal/d). Menstrual status was confirmed by measuring reproductive hormones. At baseline (0-mo) and 6-mo, two RMR measurements were made using indirect calorimetry. Energy intake (EI) and expenditure were assessed using 7-d diet and activity records, respectively. All wore an accelerometer for 7-d. Participants completed all measurements at 0-mo and 6-mo. Comparisons were made using multiple linear regression, blocking on participants. RESULTS: All women resumed menses (2.6±2.2 mo to 1 st menses, 3.5±1.9 cycles during 6-mo intervention). No significant changes, however, were observed for EA and RMR (p>0.05). Mean RMR was 1514±142 kcal/d at 0-mo and 1522±134 kcal/d at 6-mo. At 0-mo, 5 of the 8 women had an EA <30 kcal/kg LBM/d while all 8 had negative energy balance (EB). At 6-mo, these 5 women improved EA and EB, and all 8 resumed menses. Mean EA was 34±11 kcal/kg LBM/d at 0-mo and 41±15 kcal/kg LBM/d at 6-mo; mean EB was-524±410 kcal/d at 0-mo and-150±722 kcal/d at 6-mo. Mean weight changed +1.6±2.0 kg over the course of the intervention. CONCLUSION: A CHO-PRO supplement added to daily diet was effective in resuming menses in active women. Activity levels, however, varied over 6-mo making it difficult to estimate and meet energy needs to maintain menstrual status. Thus, it is difficult to define a standard EI and EA to maintain menses in endurance-trained women. Supported by Gatorade Sports Science Institute.

Medicine and Science in Sports and Exercise, May 1, 1998

Journal of The American Dietetic Association, Nov 1, 2002

The purpose of this study was to determine the concurrent validity of the BOD POD (BP) (Life Meas... more The purpose of this study was to determine the concurrent validity of the BOD POD (BP) (Life Measurement Instruments) and Dual Energy X-Ray Absorptiometry (DXA) Elite 4500A (Hologic, Inc.) techniques for assessing the body fat percentage of young women. The participants were forty-three white college-aged women (19.4 +/- 1.4 years) with a BMI of 23.4 +/- 2.3. Both body composition analyses were completed on the same day and were taken within 10 minutes of each other. Body fat percentage was estimated to be 24.3 (SE = 1.1) and 23.8 (SE = 0.8) using the BP and DXA techniques, respectively. Exact matches, in terms of body fat percentage, were obtained for 10 of the 43 participants (23.3%). In conclusion, our data supports the concurrent validity of the BP and DXA techniques for assessing body fat in young women.

Medicine and Science in Sports and Exercise, May 1, 2003

Menopause, Jul 1, 2004

Objective: To prospectively examine potential differences in upper-and lower-body muscle strength... more Objective: To prospectively examine potential differences in upper-and lower-body muscle strength, lower-body power, lean muscle mass, total body fat, intra-abdominal fat, and energy expenditure (METS) variables in early postmenopausal women. Measurements were taken at baseline and 12 months. Design: Prospective, 1-year non-randomized [self-selected hormone therapy (HT) and non-HTreplaced], longitudinal study with participation from 136 normally active, early [14.2 ± 9.8 mo past menopause (51.1 ± 3.0 y) mean age ± SD] postmenopausal women. Total body fat mass, lean mass, and bone mass were assessed by dual-energy x-ray absorptiometry (Hologic), METS (6-mo activity recall questionnaire) upper-and lower-body peak force by isokinetic dynamometry (KinCom 500H, Chattex Corp.), and leg power by the Bassey Power Rig (Nottingham, UK). Results: We observed no significant differences in central adipose tissue, total fat mass, lean muscle mass, strength, or lower limb power. However, estrogen did promote a maintenance affect in bone mineral density at the spine and total hip and an increase in greater trochanter bone mineral density (P < 0.01) in the estrogen-replaced group. Conclusion: Our findings suggest that HT does not play a role in either increasing or maintaining strength, lean muscle mass, lower limb power, or the attenuation of increases in total body or abdominal fat, at least in this group of postmenopausal women during the initial years of menopause.

Archives of Physical Medicine and Rehabilitation, Nov 1, 2011

Calcified Tissue International, Jun 1, 2000

There is evidence that high intensity resistance training promotes bone maintenance in older wome... more There is evidence that high intensity resistance training promotes bone maintenance in older women, however, the effect of high intensity free weight training has not been investigated in older men or women. Furthermore, little is known about the chronic effect of weight training on serum insulin growth factor-I (IGF-I) in this population. We compared the effects of a moderate intensity seated resistance-training program with a high intensity standing free weight exercise program on bone mass and serum levels of IGF-I and IGFBP3 in healthy older men and women. Twenty-eight men (54.6 ± 3.2 years) and 26 nonestrogenreplaced women (52.8 ± 3.3 years) served as their own controls for 12 weeks, then were randomly assigned to a moderate or high intensity training group and trained three times/week for 24 weeks. Prior to and after the control period and at the end of training, bone mass and body composition were assessed by dual energy X-ray absorptiometry (DXA), muscle strength by isokinetic dynamometry, muscular power by Wingate Anaerobic Power Test, and IGF-I by radioimmunoassay (RIA). A repeated measures analysis of covariance (ANCOVA) revealed that high intensity training resulted in a gain in spine BMD in men (1.9%), P < 0.05, but not in women, whereas moderate intensity training produced no changes in either gender at this site. Increases were observed at the greater trochanter, P < 0.03, in men regardless of training intensity, but not in women at any hip site. However, when compared with zero, both men and women in the high intensity group demonstrated significant increases in trochanteric BMD (1.3% and 2.0%, respectively) and a decrease in femoral BMD (−1.8%). Neither circulating serum IGF-I nor IGFBP3 were altered by either training regimen, but both training programs resulted in improvements in total body strength (37.62%) and lean mass (males 4.1%, females 3.1%). We conclude that although resistance training of moderate to high intensity produced similar muscle changes in older adults, a higher magnitude is necessary to stimulate osteogenesis at the spine. However, at the spine, intensity was not sufficient to offset low levels of estrogen in early postmenopausal women. Furthermore, bone changes were not accompanied by changes in circulating serum levels of IGF-I or IGFBP3.

Medicine and Science in Sports and Exercise, May 1, 1999

Medicine and Science in Sports and Exercise, May 1, 2002

Disability and Health Journal, Oct 1, 2009

Background: While physical activity is recommended to reduce symptomology associated with multipl... more Background: While physical activity is recommended to reduce symptomology associated with multiple sclerosis (MS) little has been done to explore the potential usefulness of theoretical models of exercise behavior change in individuals with MS. Based on the success of the transtheoretical model of exercise behavior change (TTM) in the general population and early promising results in those with MS, the TTM was tested in a sample of women with MS over a 1-year period, to examine its usefulness and the effect of TTM constructs on MS-related symptoms. Methods: This was a longitudinal study conducted over a 1-year period. Ambulatory women (N 5 86) with MS completed questionnaires assessing exercise behavior, TTM constructs, MS-related quality of life, pain, and fatigue at baseline and after 1 year. After categorization into transitional shift patterns reflecting naturally occurring exercise behavior change over the year, a series of mixed-design analyses of variance were conducted to examine TTM predictions and the relationship of the transitional shift patterns to MS-related quality of life, pain, and fatigue. Results: Significant interactions between transitional shift patterns and time (P ! .05) indicated that changes in behavioral and cognitive processes of change and in self-efficacy were consistent with TTM predictions. Significant differences (P ! .05) between the transitional shift groups in pain and fatigue in expected directions were also found. Conclusions: Results supported the TTM proposed relationships, indicating the model's potential for motivating individuals with MS to increase their physical activity. Findings also support the notion that physical activity is useful in reducing MS-related symptoms and that lifestyle types of physical activity may be as useful as structured exercise in bringing about these outcomes.

Medicine and Science in Sports and Exercise, May 1, 2004

Medicine and Science in Sports and Exercise, May 1, 2003

International Journal of Obesity, Jul 29, 2008

Objective-To evaluate the effects of whole-body vibration on fat, bone, leptin and muscle mass. M... more Objective-To evaluate the effects of whole-body vibration on fat, bone, leptin and muscle mass. Methods/Design-Thirty 7-month-old female 344 Fischer rats were randomized by weight into three groups (baseline, vibration or control; n=7-10 per group). Rats in the vibration group were placed inside individual compartments attached to a Pneu-Vibe vibration platform (Pneumex, Sandpoint, ID, USA) and vibrated at 30-50 Hz (6mm peak to peak) for 30 min per day, 5 days per week, for 12 weeks. The vibration intervention consisted of six 5-min cycles with a 1-min break between cycles. Results-There were significant body composition differences between the whole-body vibration and the control groups. The whole-body vibration group weighed approximately 10% less (mean ± s.d.; 207 ± 10 vs 222 ± 15 g, P<0.03) and had less body fat (20.8 ± 3.8 vs 26.8 ± 5.9 g, P<0.05), a lower percentage of body fat (10.2 ± 1.7 vs 12 ± 2.0%, P<0.05), and lower serum leptin levels (1.06 ± 0.45 vs 2.27 ± 0.57 ng ml −1 , P<0.01) than the age-matched controls. No differences were observed for total lean mass, bone mineral content (BMC), bone mineral density (BMD), insulin-like growth factor-I (IGF-I) or soleus (SOL) and extensor digitorum longus (EDL) mass or function. Regional high-resolution dual-energy X-ray absoptiometry scans of the lumbar spine (L1-4) revealed that the whole-body vibration group had significantly greater BMC (0.33 ± 0.05 vs 0.26 ± 0.03 g, P<0.01) and BMD (0.21 ± 0.01 vs 0.19 ± 0.01 gcm −2 , P<0.01) than the control group. No differences between the groups were observed in the amount of food consumed. Conclusion-These findings show that whole-body vibration reduced body fat accumulation and serum leptin without affecting whole body BMC, BMD or lean mass. However, the increase in vertebral BMC and BMD suggests that vibration may have resulted in local increases in bone mass and density. Also, whole-body vibration did not affect muscle function or food consumption.

PubMed, 2003

Background: Estrogen receptors have been located in the human spinal cord and the dorsal root gan... more Background: Estrogen receptors have been located in the human spinal cord and the dorsal root ganglia. The location of these receptors may allow them to participate in motoneuron regulation. Estrogen has the capability to exhibit a strong influence on cells of the nervous system. Objective: To determine whether differences exist in spinal reflex profiles between early postmenopausal women taking hormone replacement therapy and those who are not. Methods: Spinal reflex profiles (maximum H-reflex/maximum M-wave) provide insight into the connectiveness of the sensory and motor components of the reflex loop. The maximum H-reflex/maximum M-wave ratios were assessed in 40 early postmenopausal women divided into two groups--hormone replacement therapy and no hormone replacement therapy. Results: Our results indicate that no group differences in spinal reflex profiles existed between women in this study who were taking hormone replacement therapy and those who were not taking hormone replacement therapy. Conclusion: These results lead to the conclusion that a woman's choice regarding hormone replacement therapy did not affect the connections of the components of the spinal reflex loop in the women in this study.

Medicine and Science in Sports and Exercise, May 1, 2002

Medicine and Science in Sports and Exercise, May 1, 2002

International Journal of Obesity, Jan 20, 2009

Objective-To evaluate the effects of whole-body vibration on fat, bone, leptin and muscle mass. M... more Objective-To evaluate the effects of whole-body vibration on fat, bone, leptin and muscle mass. Methods/Design-Thirty 7-month-old female 344 Fischer rats were randomized by weight into three groups (baseline, vibration or control; n=7-10 per group). Rats in the vibration group were placed inside individual compartments attached to a Pneu-Vibe vibration platform (Pneumex, Sandpoint, ID, USA) and vibrated at 30-50 Hz (6mm peak to peak) for 30 min per day, 5 days per week, for 12 weeks. The vibration intervention consisted of six 5-min cycles with a 1-min break between cycles. Results-There were significant body composition differences between the whole-body vibration and the control groups. The whole-body vibration group weighed approximately 10% less (mean ± s.d.; 207 ± 10 vs 222 ± 15 g, P<0.03) and had less body fat (20.8 ± 3.8 vs 26.8 ± 5.9 g, P<0.05), a lower percentage of body fat (10.2 ± 1.7 vs 12 ± 2.0%, P<0.05), and lower serum leptin levels (1.06 ± 0.45 vs 2.27 ± 0.57 ng ml −1 , P<0.01) than the age-matched controls. No differences were observed for total lean mass, bone mineral content (BMC), bone mineral density (BMD), insulin-like growth factor-I (IGF-I) or soleus (SOL) and extensor digitorum longus (EDL) mass or function. Regional high-resolution dual-energy X-ray absoptiometry scans of the lumbar spine (L1-4) revealed that the whole-body vibration group had significantly greater BMC (0.33 ± 0.05 vs 0.26 ± 0.03 g, P<0.01) and BMD (0.21 ± 0.01 vs 0.19 ± 0.01 gcm −2 , P<0.01) than the control group. No differences between the groups were observed in the amount of food consumed. Conclusion-These findings show that whole-body vibration reduced body fat accumulation and serum leptin without affecting whole body BMC, BMD or lean mass. However, the increase in vertebral BMC and BMD suggests that vibration may have resulted in local increases in bone mass and density. Also, whole-body vibration did not affect muscle function or food consumption.

Medicine and Science in Sports and Exercise, May 1, 2002

Chapter I moderate intensity training produced no change at this site. Neither circulating IGF-I ... more Chapter I moderate intensity training produced no change at this site. Neither circulating IGF-I nor IGFBP3 were altered by either training regimen, but both training programs resulted in improvements in total body strength (37.62%), lean mass (males 4.1%, females 2.7%) and leg lean mass (3.3%) regardless of gender. Results demonstrate that high intensity training produced a shift in mineral at the hip for both men and women, increased spine BMD in men but not women, and niaintained whole body BMD in both genders. These improvements were not accompanied by changes in circulating levels of IGF-I, IGFBP3 or IGF-IIIGFBP3. Although resistance training of moderate to high intensity produced similar muscle changes in younger older adults, a higher magnitude is necessary to stimulate osteogenesis. The redistribution at the hip indicates a highly-specific response to mechanical loads at this site. The long-term implication of this response is unclear, but in may confer some protection from trochanteric fractures.

Alcoholism: Clinical and Experimental Research, Sep 17, 2019

Background:Estrogen signaling is essential for the sexual dimorphism of the skeleton, is required... more Background:Estrogen signaling is essential for the sexual dimorphism of the skeleton, is required for normal bone remodeling balance in adults, and may influence the skeletal response to alcohol. High levels of alcohol consumption lower bone mass in ovary-intact but not ovariectomized (ovx) rats. However, the extremely rapid rate of bone loss immediately following ovx may obscure the effects of alcohol. We therefore determined (1) whether heavy alcohol consumption (35% caloric intake) influences bone in sexually mature ovx rats with established cancellous osteopenia, and (2) whether ICI 182,780 (ICI), a potent estrogen receptor-signaling antagonist, alters the skeletal response to alcohol.Methods:Three weeks following ovx, rats were randomized into five groups: (1) baseline, (2) control+vehicle, (3) control+ICI, (4) ethanol+vehicle, or (5) ethanol+ICI and treated accordingly for four weeks. Dual energy X-ray absorptiometry, micro-computed tomography, blood measurements of markers of bone turnover, and gene expression in femur and uterus were used to evaluate response to alcohol and ICI.Results:Rats consuming alcohol had lower bone mass and increased fat mass. Bone microarchitecture of the tibia and gene expression in femur were altered; specifically, there was reduced accrual of cortical bone, net loss of cancellous bone, and differential expression of 19/84 genes related to bone turnover. Furthermore, osteocalcin, a marker of bone turnover, was lower in alcohol-fed rats. ICI had no effect on weight gain, body composition, or cortical bone. ICI reduced cancellous bone loss and serum CTX-1, a biochemical marker of bone resorption; alcohol antagonized the latter two responses. Neither alcohol nor ICI affected uterine weight or gene expression.Conclusion:Alcohol exaggerated bone loss in ovx rats in the presence or absence of estrogen receptor blockade with ICI. The negligible effect of alcohol on uterus and limited effects of ICI on bone in alcohol-fed ovx rats suggests that estrogen receptor signaling plays a limited role in the action of alcohol on bone in a rat model for chronic alcohol abuse.

Medicine and Science in Sports and Exercise, May 1, 2011

To determine if the restoration of menses in endurance-trained women, using a daily carbohydrate-... more To determine if the restoration of menses in endurance-trained women, using a daily carbohydrate-protein (CHO-PRO) supplement, is associated with improvements in EA and RMR. METHODS: Active women with ExMD (n=8; 7 amenorrheic, 1 oligomenorrheic, age=23±3y, VO2max=49±6 mL/kg/min, body fat=22±4%) participated in a 6-mo intervention and consumed 325 mL/d of CHO-PRO supplement (360 kcal/d). Menstrual status was confirmed by measuring reproductive hormones. At baseline (0-mo) and 6-mo, two RMR measurements were made using indirect calorimetry. Energy intake (EI) and expenditure were assessed using 7-d diet and activity records, respectively. All wore an accelerometer for 7-d. Participants completed all measurements at 0-mo and 6-mo. Comparisons were made using multiple linear regression, blocking on participants. RESULTS: All women resumed menses (2.6±2.2 mo to 1 st menses, 3.5±1.9 cycles during 6-mo intervention). No significant changes, however, were observed for EA and RMR (p>0.05). Mean RMR was 1514±142 kcal/d at 0-mo and 1522±134 kcal/d at 6-mo. At 0-mo, 5 of the 8 women had an EA <30 kcal/kg LBM/d while all 8 had negative energy balance (EB). At 6-mo, these 5 women improved EA and EB, and all 8 resumed menses. Mean EA was 34±11 kcal/kg LBM/d at 0-mo and 41±15 kcal/kg LBM/d at 6-mo; mean EB was-524±410 kcal/d at 0-mo and-150±722 kcal/d at 6-mo. Mean weight changed +1.6±2.0 kg over the course of the intervention. CONCLUSION: A CHO-PRO supplement added to daily diet was effective in resuming menses in active women. Activity levels, however, varied over 6-mo making it difficult to estimate and meet energy needs to maintain menstrual status. Thus, it is difficult to define a standard EI and EA to maintain menses in endurance-trained women. Supported by Gatorade Sports Science Institute.

Medicine and Science in Sports and Exercise, May 1, 1998

Journal of The American Dietetic Association, Nov 1, 2002

The purpose of this study was to determine the concurrent validity of the BOD POD (BP) (Life Meas... more The purpose of this study was to determine the concurrent validity of the BOD POD (BP) (Life Measurement Instruments) and Dual Energy X-Ray Absorptiometry (DXA) Elite 4500A (Hologic, Inc.) techniques for assessing the body fat percentage of young women. The participants were forty-three white college-aged women (19.4 +/- 1.4 years) with a BMI of 23.4 +/- 2.3. Both body composition analyses were completed on the same day and were taken within 10 minutes of each other. Body fat percentage was estimated to be 24.3 (SE = 1.1) and 23.8 (SE = 0.8) using the BP and DXA techniques, respectively. Exact matches, in terms of body fat percentage, were obtained for 10 of the 43 participants (23.3%). In conclusion, our data supports the concurrent validity of the BP and DXA techniques for assessing body fat in young women.

Medicine and Science in Sports and Exercise, May 1, 2003

Menopause, Jul 1, 2004

Objective: To prospectively examine potential differences in upper-and lower-body muscle strength... more Objective: To prospectively examine potential differences in upper-and lower-body muscle strength, lower-body power, lean muscle mass, total body fat, intra-abdominal fat, and energy expenditure (METS) variables in early postmenopausal women. Measurements were taken at baseline and 12 months. Design: Prospective, 1-year non-randomized [self-selected hormone therapy (HT) and non-HTreplaced], longitudinal study with participation from 136 normally active, early [14.2 ± 9.8 mo past menopause (51.1 ± 3.0 y) mean age ± SD] postmenopausal women. Total body fat mass, lean mass, and bone mass were assessed by dual-energy x-ray absorptiometry (Hologic), METS (6-mo activity recall questionnaire) upper-and lower-body peak force by isokinetic dynamometry (KinCom 500H, Chattex Corp.), and leg power by the Bassey Power Rig (Nottingham, UK). Results: We observed no significant differences in central adipose tissue, total fat mass, lean muscle mass, strength, or lower limb power. However, estrogen did promote a maintenance affect in bone mineral density at the spine and total hip and an increase in greater trochanter bone mineral density (P < 0.01) in the estrogen-replaced group. Conclusion: Our findings suggest that HT does not play a role in either increasing or maintaining strength, lean muscle mass, lower limb power, or the attenuation of increases in total body or abdominal fat, at least in this group of postmenopausal women during the initial years of menopause.

Archives of Physical Medicine and Rehabilitation, Nov 1, 2011

Calcified Tissue International, Jun 1, 2000

There is evidence that high intensity resistance training promotes bone maintenance in older wome... more There is evidence that high intensity resistance training promotes bone maintenance in older women, however, the effect of high intensity free weight training has not been investigated in older men or women. Furthermore, little is known about the chronic effect of weight training on serum insulin growth factor-I (IGF-I) in this population. We compared the effects of a moderate intensity seated resistance-training program with a high intensity standing free weight exercise program on bone mass and serum levels of IGF-I and IGFBP3 in healthy older men and women. Twenty-eight men (54.6 ± 3.2 years) and 26 nonestrogenreplaced women (52.8 ± 3.3 years) served as their own controls for 12 weeks, then were randomly assigned to a moderate or high intensity training group and trained three times/week for 24 weeks. Prior to and after the control period and at the end of training, bone mass and body composition were assessed by dual energy X-ray absorptiometry (DXA), muscle strength by isokinetic dynamometry, muscular power by Wingate Anaerobic Power Test, and IGF-I by radioimmunoassay (RIA). A repeated measures analysis of covariance (ANCOVA) revealed that high intensity training resulted in a gain in spine BMD in men (1.9%), P < 0.05, but not in women, whereas moderate intensity training produced no changes in either gender at this site. Increases were observed at the greater trochanter, P < 0.03, in men regardless of training intensity, but not in women at any hip site. However, when compared with zero, both men and women in the high intensity group demonstrated significant increases in trochanteric BMD (1.3% and 2.0%, respectively) and a decrease in femoral BMD (−1.8%). Neither circulating serum IGF-I nor IGFBP3 were altered by either training regimen, but both training programs resulted in improvements in total body strength (37.62%) and lean mass (males 4.1%, females 3.1%). We conclude that although resistance training of moderate to high intensity produced similar muscle changes in older adults, a higher magnitude is necessary to stimulate osteogenesis at the spine. However, at the spine, intensity was not sufficient to offset low levels of estrogen in early postmenopausal women. Furthermore, bone changes were not accompanied by changes in circulating serum levels of IGF-I or IGFBP3.

Medicine and Science in Sports and Exercise, May 1, 1999

Medicine and Science in Sports and Exercise, May 1, 2002

Disability and Health Journal, Oct 1, 2009

Background: While physical activity is recommended to reduce symptomology associated with multipl... more Background: While physical activity is recommended to reduce symptomology associated with multiple sclerosis (MS) little has been done to explore the potential usefulness of theoretical models of exercise behavior change in individuals with MS. Based on the success of the transtheoretical model of exercise behavior change (TTM) in the general population and early promising results in those with MS, the TTM was tested in a sample of women with MS over a 1-year period, to examine its usefulness and the effect of TTM constructs on MS-related symptoms. Methods: This was a longitudinal study conducted over a 1-year period. Ambulatory women (N 5 86) with MS completed questionnaires assessing exercise behavior, TTM constructs, MS-related quality of life, pain, and fatigue at baseline and after 1 year. After categorization into transitional shift patterns reflecting naturally occurring exercise behavior change over the year, a series of mixed-design analyses of variance were conducted to examine TTM predictions and the relationship of the transitional shift patterns to MS-related quality of life, pain, and fatigue. Results: Significant interactions between transitional shift patterns and time (P ! .05) indicated that changes in behavioral and cognitive processes of change and in self-efficacy were consistent with TTM predictions. Significant differences (P ! .05) between the transitional shift groups in pain and fatigue in expected directions were also found. Conclusions: Results supported the TTM proposed relationships, indicating the model's potential for motivating individuals with MS to increase their physical activity. Findings also support the notion that physical activity is useful in reducing MS-related symptoms and that lifestyle types of physical activity may be as useful as structured exercise in bringing about these outcomes.

Medicine and Science in Sports and Exercise, May 1, 2004

Medicine and Science in Sports and Exercise, May 1, 2003

International Journal of Obesity, Jul 29, 2008

Objective-To evaluate the effects of whole-body vibration on fat, bone, leptin and muscle mass. M... more Objective-To evaluate the effects of whole-body vibration on fat, bone, leptin and muscle mass. Methods/Design-Thirty 7-month-old female 344 Fischer rats were randomized by weight into three groups (baseline, vibration or control; n=7-10 per group). Rats in the vibration group were placed inside individual compartments attached to a Pneu-Vibe vibration platform (Pneumex, Sandpoint, ID, USA) and vibrated at 30-50 Hz (6mm peak to peak) for 30 min per day, 5 days per week, for 12 weeks. The vibration intervention consisted of six 5-min cycles with a 1-min break between cycles. Results-There were significant body composition differences between the whole-body vibration and the control groups. The whole-body vibration group weighed approximately 10% less (mean ± s.d.; 207 ± 10 vs 222 ± 15 g, P<0.03) and had less body fat (20.8 ± 3.8 vs 26.8 ± 5.9 g, P<0.05), a lower percentage of body fat (10.2 ± 1.7 vs 12 ± 2.0%, P<0.05), and lower serum leptin levels (1.06 ± 0.45 vs 2.27 ± 0.57 ng ml −1 , P<0.01) than the age-matched controls. No differences were observed for total lean mass, bone mineral content (BMC), bone mineral density (BMD), insulin-like growth factor-I (IGF-I) or soleus (SOL) and extensor digitorum longus (EDL) mass or function. Regional high-resolution dual-energy X-ray absoptiometry scans of the lumbar spine (L1-4) revealed that the whole-body vibration group had significantly greater BMC (0.33 ± 0.05 vs 0.26 ± 0.03 g, P<0.01) and BMD (0.21 ± 0.01 vs 0.19 ± 0.01 gcm −2 , P<0.01) than the control group. No differences between the groups were observed in the amount of food consumed. Conclusion-These findings show that whole-body vibration reduced body fat accumulation and serum leptin without affecting whole body BMC, BMD or lean mass. However, the increase in vertebral BMC and BMD suggests that vibration may have resulted in local increases in bone mass and density. Also, whole-body vibration did not affect muscle function or food consumption.

PubMed, 2003

Background: Estrogen receptors have been located in the human spinal cord and the dorsal root gan... more Background: Estrogen receptors have been located in the human spinal cord and the dorsal root ganglia. The location of these receptors may allow them to participate in motoneuron regulation. Estrogen has the capability to exhibit a strong influence on cells of the nervous system. Objective: To determine whether differences exist in spinal reflex profiles between early postmenopausal women taking hormone replacement therapy and those who are not. Methods: Spinal reflex profiles (maximum H-reflex/maximum M-wave) provide insight into the connectiveness of the sensory and motor components of the reflex loop. The maximum H-reflex/maximum M-wave ratios were assessed in 40 early postmenopausal women divided into two groups--hormone replacement therapy and no hormone replacement therapy. Results: Our results indicate that no group differences in spinal reflex profiles existed between women in this study who were taking hormone replacement therapy and those who were not taking hormone replacement therapy. Conclusion: These results lead to the conclusion that a woman's choice regarding hormone replacement therapy did not affect the connections of the components of the spinal reflex loop in the women in this study.

Medicine and Science in Sports and Exercise, May 1, 2002

Medicine and Science in Sports and Exercise, May 1, 2002

International Journal of Obesity, Jan 20, 2009

Objective-To evaluate the effects of whole-body vibration on fat, bone, leptin and muscle mass. M... more Objective-To evaluate the effects of whole-body vibration on fat, bone, leptin and muscle mass. Methods/Design-Thirty 7-month-old female 344 Fischer rats were randomized by weight into three groups (baseline, vibration or control; n=7-10 per group). Rats in the vibration group were placed inside individual compartments attached to a Pneu-Vibe vibration platform (Pneumex, Sandpoint, ID, USA) and vibrated at 30-50 Hz (6mm peak to peak) for 30 min per day, 5 days per week, for 12 weeks. The vibration intervention consisted of six 5-min cycles with a 1-min break between cycles. Results-There were significant body composition differences between the whole-body vibration and the control groups. The whole-body vibration group weighed approximately 10% less (mean ± s.d.; 207 ± 10 vs 222 ± 15 g, P<0.03) and had less body fat (20.8 ± 3.8 vs 26.8 ± 5.9 g, P<0.05), a lower percentage of body fat (10.2 ± 1.7 vs 12 ± 2.0%, P<0.05), and lower serum leptin levels (1.06 ± 0.45 vs 2.27 ± 0.57 ng ml −1 , P<0.01) than the age-matched controls. No differences were observed for total lean mass, bone mineral content (BMC), bone mineral density (BMD), insulin-like growth factor-I (IGF-I) or soleus (SOL) and extensor digitorum longus (EDL) mass or function. Regional high-resolution dual-energy X-ray absoptiometry scans of the lumbar spine (L1-4) revealed that the whole-body vibration group had significantly greater BMC (0.33 ± 0.05 vs 0.26 ± 0.03 g, P<0.01) and BMD (0.21 ± 0.01 vs 0.19 ± 0.01 gcm −2 , P<0.01) than the control group. No differences between the groups were observed in the amount of food consumed. Conclusion-These findings show that whole-body vibration reduced body fat accumulation and serum leptin without affecting whole body BMC, BMD or lean mass. However, the increase in vertebral BMC and BMD suggests that vibration may have resulted in local increases in bone mass and density. Also, whole-body vibration did not affect muscle function or food consumption.

Medicine and Science in Sports and Exercise, May 1, 2002

Chapter I moderate intensity training produced no change at this site. Neither circulating IGF-I ... more Chapter I moderate intensity training produced no change at this site. Neither circulating IGF-I nor IGFBP3 were altered by either training regimen, but both training programs resulted in improvements in total body strength (37.62%), lean mass (males 4.1%, females 2.7%) and leg lean mass (3.3%) regardless of gender. Results demonstrate that high intensity training produced a shift in mineral at the hip for both men and women, increased spine BMD in men but not women, and niaintained whole body BMD in both genders. These improvements were not accompanied by changes in circulating levels of IGF-I, IGFBP3 or IGF-IIIGFBP3. Although resistance training of moderate to high intensity produced similar muscle changes in younger older adults, a higher magnitude is necessary to stimulate osteogenesis. The redistribution at the hip indicates a highly-specific response to mechanical loads at this site. The long-term implication of this response is unclear, but in may confer some protection from trochanteric fractures.