CNR - Institute of Neuroscience CNR
Institute of Neuroscience
 

Project

High frequency vibration training in menopausal women with type 2 diabetes

Introduction

When glycemic control is not satisfactory, type 2 diabetes (T2DM) is accompanied by micro- and macroangiopathic complications. It is a well known fact that patients with T2DM are often overweight and not involved in regular physical activities, in fact among women aged ≥65 years with diabetes there is a high incidence of inability to perform physical and household tasks.

Sarcopenia is a condition responsible for bone mass loss and bone fragility, with an age-related decline in muscle mass resulting in slow walking speed, low physical activity, decreased exercise tolerance, increased fall rates, and decreased bone strength. Sarcopenia affects more often women, because of a lower baseline total muscle mass, and an increased rate of loss of muscle mass in postmenopausal period. Women reach critical threshold of muscle mass loss and weakness more quicklycompared to men.

Despite having a higher bone density, on average, women with diabetes had a higher risk of hip and proximal humerus fractures. Probably diabetes is associated with a decrease in bone quality that is not reflected in the measurement of bone mineral density (BMD). Other factors, associated with frailty and fracture, including falls, and chronic complications of diabetes do not completely account for the association between diabetes and fracture. T2DM is associated with an alteration in the bone quality due to a low rates of bone turnover.

Mechanically generated electrical forces can influence the quality of bone (density, strength and architecture) and muscular activity stimulate the new bone formation, therefore forces generated by muscle contractions could be an important determinant of bone quality. In particular, high frequency vibration (HFV) is a special form of physical exercise especially suitable for T2DM, overweight patients. It entail short training sessions, produces a moderate, highly predictable oxygen-uptake, and no special skills are necessary. HFV increases muscular strength promoting spontaneous physical activity and it may be efficacious in improving bone quality by stimulating muscular activity.

Rationale

Regular physical activity using a vibrating platform seems to improve glycemic control and cardiovascular performance. It also seems to prevent muscular atrophy, can cause a modification in body composition and improve bone structure and density. But there are few clinical studies on vibration exercises in diabetic subjects.

The objective is to verify if HFV exercise on a platform can improve glycemic control, diastolic function, muscular and hematochemical parameters, bone mineral density, and body composition in menopausal women with T2DM.

Methods

A randomized, controlled intervention trial is underway. Inclusion criteria: menopausal women, who have been affected with T2DM for at least a year and with weight variations <3 kg over the last 3 months. Exclusion criteria: Cardio-cerebrovascular events in the last 6 months, pacemaker, serious arrhythmias, deep vein thrombosis; chronic dizziness syndrome; advanced stages of malignant cancers; fractures in the last 2 months, acute disc herniation; chronic conditions including dementia, alcoholism, dialysis, haemorrhage; already participating in a program of regular, intense physical activity.

Patients perform a baseline evaluation and are randomized into two groups: the Intervention (I, n=25) or the Control (C, n=25) group.

The Baseline assessment includes general examinations, vital signs, EKG, and determination of glycemic, metabolic, muscular, bone and inflammatory parameters. Physical performance, body composition (total body DXA), bone mineral density (DXA), parameters of diastolic dysfunction of the left ventricle (echocardiography) are evaluated.

Intervention: The I group is undergo 6 months of HFV training (20-25 Hz) on a NEMES Bosco System platform. Two weekly sessions made up of 5 repetitions each lasting one minute of vibration and one minute of resting. The C group, undergone the same baseline evaluation, is invited to maintain its regular physical activity regime for the duration of the study.

Intermediate and final evaluations are carried out after 12±1 and 24±2 weeks and the patients perform the same exams with the exception of the DXA and echocardiography which are repeated only at the end of the study. The association between baseline characteristics and groups will be evaluated using the χ2 or Fisher's exact test, GLM procedure. The differences in the parameters at baseline and at the follow-ups between the two groups will be evaluated using the t test and the Wilcoxon rank-sum test (α=0.05, bilateral).

Preliminary results

 

The study is presently underway: 33 patients (22 in group I and 11 in C) are signed up, and 6 are dropped out. The mean age is 65.1±10 in the I group and 69.8±7 in the C group. The BMI is 32.6±5.6 in the I group and 29.7±1.4 Kg/m2 in the C group. Both groups show a Vitamin D insufficiency (I group= 42±31; C group= 43±33 nmol/l). The first 12 patients in the I group, who carried out the 6 months follow-up, show a significant decrease in the mean value of glucose (from 8.75±2.1 to 6.8±1.5 nmol/l, p=0.037), of total cholesterol (from 192±34 to 185±30 mg/dl p=0.047) and of triglycerides (from123±25 to 100±29 mg/dl, p=0.005). No differences are reported in HbA1c, insulin, Vit D, PTH level in the I group.

 

The patients in the I group show a significant reduction in the Trunk Fat from baseline to the 3 (p=0.035) and 6 mounts (p=0.032) follow-up, in the Total Fat Mass from baseline to the 3 (p=0.047) and 6 mounts (p=0.032) follow-up and also in the Total Mass from baseline to the 6 months follow-up (p=0.04). Wilcoxon test (Figure 1, 2 and 3)

Among patients, who carried out the 6 months follow-up, there is a significant increase in the mean value of vertebral BMD in comparison with the value at baseline (p=0.034), while there is no variations in the mean value of the femoral BMD in comparison with the baseline evaluation. Wilcoxon test (Figure 4)

 
 

Conclusions

Preliminary results show an improvement both in some metabolic parameters, and some parameters of bone metabolism and body composition. These initial findings are encouraging, it will be appropriate to continue the study and to perform comparisons with the control group.

Publications

  • Saller A, Maggi S, Romanato G, Tonin P, Crepaldi G (2008) Diabetes and osteoporosis. 20:280-9.
  • Maggi S, Noale M, Gallina P, Marzari C, Bianchi D, Limongi F, Crepaldi G, (2004) Physical disability among older Italians with diabetes. The ILSA study. Diabetologia 47:1957-62.
  • 15506693 [Warning: check DB]

Collaborations

  • R. Betto, CNR-IN-Padua, Italy.
  • G. Sergi and A. Coin, Geriatric Department, University of Padua, Italy.

 

PI photo

Stefania Maggi

Contact information

email  E-mail

email  049 8211746

Participating staff

G. Romanato

A. Saller

E. Manzato