Effects of Functional Electrical Stimulation on Metaboreflex Activation in Healthy Individuals

NCT ID: NCT02448030

Last Updated: 2015-05-20

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: EARLY_PHASE1
• Total Enrollment: 20 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2015-03-31
• Study Completion Date: 2016-03-31

Brief Summary

Cardiovascular exercise adjustments are required during in order to redistribute blood flow from non-exercising vascular areas to active muscles. This hemodynamic adjustments, which are partially mediated by mechanosensitive and metabosensitive reflexes, ultimately increase oxygen and nutrient delivery to exercising muscle tissues (Mitchell, 1990). Static handgrip exercise has been shown to induce alterations in the arterial baroreflex function (Kim, 2005) and activation of muscle metaboreflex that increases arterial blood pressure and peripheral vasoconstriction, respectively. Functional electrical stimulation (FES) treatment used in physical therapy in patients who are unable to tolerate conventional exercise showed to be a good alternative for muscle strengthening (Sbruzzi, 2010) and to improve metabolic abnormalities (Karavidas, 2006). However, the effect of FES on metaboreflex activation in healthy individuals has never been investigated. Therefore, this study aims to evaluate the metaboreflex activation induced by FES in upper and low limbs in healthy individuals, and also to compare their results with the effects caused by isometric exercise.

Detailed Description

All participants will be invited to attend four separate days for completion of the study protocols. On the first day, the metaboreflex activation in upper limb will be randomly assigned to isometric exercise or FES intervention. On the second day, at least two days apart, random isometric exercise or FES intervention will be performed in the upper limb. On the third day, at least one week apart, all participants will be assigned to perform metaboreflex in a lower limb induced by isometric exercise or FES intervention. On the fourth day, at least two days apart, random isometric exercise or FES intervention will be performed in a lower limb. To evaluate the isometric exercise and FES intervention the post-exercise ischemia will be randomly performed to evaluate the accumulation of metabolites in response to activated limb (PECO +) and evaluation control without ischemia (PECO-). The experiments between PECO+ and PECO- will be separated by a 30 min interval. During isometric exercise and FES protocols the blood flow and peripheral vascular resistance will be assessed by venous occlusion plethysmography. Fatigue will be determined every minute by the 10-point Borg scale to assess rate of perceived exertion and by blood lactate. Blood lactate will be evaluated through capillary action at pre, immediately post exercise and at 5 minutes during the recovery period. Hemodynamic variables such as BP and HR will be recorded every minute during the protocols.

Conditions

Reduction of Blood Flow

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

Functional electric stimulation

Other: The FES will be placed at the flexor muscles of the forearm and knee extensors, for evaluation of upper and lower limbs, respectively.

Group Type: EXPERIMENTAL

Functional electric stimulation

Intervention Type: OTHER

The FES will be placed at the flexor muscles of the forearm and knee extensors, for evaluation of upper and lower limbs, respectively. The stimulation frequency will be 20 Hz. The pulse width used will be 0.5 milliseconds and the contraction time will be 60 seconds (TON: 60s) with a 1-second rest interval (TOFF: 1s). The total time of application will be determined for the muscle fatigue that will be evaluated by 10-point Borg scale and by the measurement of lactate accumulation that must not exceed 30 minutes. The intensity will be adjusted individually, taking into account the patient's ability to promote the full flexion of the wrist / knee extension and comfort during contractions. Along with the application of FES a 1 Kg overload will be applied to intensify the fatigue time.

Isometric exercise

For the upper limbs the isometric contraction exercise with handgrip will be performed for 5 minutes with 30% of loading, previously measured by maximum voluntary contraction test.

Group Type: PLACEBO_COMPARATOR

Isometric exercise

Intervention Type: OTHER

For the upper limbs the isometric contraction exercise with handgrip will be performed for 5 minutes with 30% of loading, previously measured by maximum voluntary contraction test. For the lower limbs the knee extension exercise will be conducted in a training station. The SBP, DBP, MBP and HR will be recorded through the protocols. Fatigue will be determined every minute by the 10-point Borg scale and by measurement of lactate accumulation before, immediately after the protocol, and 5 minutes during the recovery period.

Interventions

Functional electric stimulation

The FES will be placed at the flexor muscles of the forearm and knee extensors, for evaluation of upper and lower limbs, respectively. The stimulation frequency will be 20 Hz. The pulse width used will be 0.5 milliseconds and the contraction time will be 60 seconds (TON: 60s) with a 1-second rest interval (TOFF: 1s). The total time of application will be determined for the muscle fatigue that will be evaluated by 10-point Borg scale and by the measurement of lactate accumulation that must not exceed 30 minutes. The intensity will be adjusted individually, taking into account the patient's ability to promote the full flexion of the wrist / knee extension and comfort during contractions. Along with the application of FES a 1 Kg overload will be applied to intensify the fatigue time.

Intervention Type: OTHER

Isometric exercise

For the upper limbs the isometric contraction exercise with handgrip will be performed for 5 minutes with 30% of loading, previously measured by maximum voluntary contraction test. For the lower limbs the knee extension exercise will be conducted in a training station. The SBP, DBP, MBP and HR will be recorded through the protocols. Fatigue will be determined every minute by the 10-point Borg scale and by measurement of lactate accumulation before, immediately after the protocol, and 5 minutes during the recovery period.

Intervention Type: OTHER

Other Intervention Names

FES

Eligibility Criteria

Inclusion Criteria

• Healthy individuals
• Both genders
• Aged 35-70 years
• Sedentary
• Not using continuous medications

Exclusion Criteria

• Cardiovascular disease
• Neurological disease
• Malignant disease
• Peripheral vascular disorders (varicose veins or deep vein thrombosis)
• Peripheral sensitivity alterations
• Contraindication to performing physical exercise
• Refusal to sign the consent form

• Minimum Eligible Age: 35 Years
• Maximum Eligible Age: 70 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Hospital de Clinicas de Porto Alegre

OTHER

Sponsor Role: lead

Responsible Party

Beatriz D'Agord Schaan

Doctor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Beatriz Dr Schaan, PhD

Role: PRINCIPAL_INVESTIGATOR

Hospital de Clinicas de Porto Alegre

Aline Macedo, Graduate

Role: STUDY_CHAIR

Federal University of Rio Grande do Sul

Locations

Hospital de Clinicas de Porto Alegre

Porto Alegre, Rio Grande do Sul, Brazil

Site Status: RECRUITING

Countries

Brazil

Central Contacts

Beatriz Dr Schaan, PhD

Role: CONTACT

beatrizschaan@gmail.com

+55 5193138534

Aline Dr Macedo, Graduate

Role: CONTACT

alinechagastelles@gmail.com

+55 5197016966

Facility Contacts

Aline Macedo, Graduate

Role: primary

alinechagastelles@gmail.com

+55 51 97016966

References

Mitchell JH. J.B. Wolffe memorial lecture. Neural control of the circulation during exercise. Med Sci Sports Exerc. 1990 Apr;22(2):141-54. No abstract available.

Reference Type: BACKGROUND

PMID: 2192221 (View on PubMed)

Rowell LB, O'Leary DS. Reflex control of the circulation during exercise: chemoreflexes and mechanoreflexes. J Appl Physiol (1985). 1990 Aug;69(2):407-18. doi: 10.1152/jappl.1990.69.2.407.

Reference Type: BACKGROUND

PMID: 2228848 (View on PubMed)

Kim JK, Sala-Mercado JA, Rodriguez J, Scislo TJ, O'Leary DS. Arterial baroreflex alters strength and mechanisms of muscle metaboreflex during dynamic exercise. Am J Physiol Heart Circ Physiol. 2005 Mar;288(3):H1374-80. doi: 10.1152/ajpheart.01040.2004. Epub 2004 Nov 11.

Reference Type: BACKGROUND

PMID: 15539416 (View on PubMed)

Sbruzzi G, Ribeiro RA, Schaan BD, Signori LU, Silva AM, Irigoyen MC, Plentz RD. Functional electrical stimulation in the treatment of patients with chronic heart failure: a meta-analysis of randomized controlled trials. Eur J Cardiovasc Prev Rehabil. 2010 Jun;17(3):254-60. doi: 10.1097/HJR.0b013e328339b5a2.

Reference Type: BACKGROUND

PMID: 20560163 (View on PubMed)

Karavidas AI, Raisakis KG, Parissis JT, Tsekoura DK, Adamopoulos S, Korres DA, Farmakis D, Zacharoulis A, Fotiadis I, Matsakas E, Zacharoulis A. Functional electrical stimulation improves endothelial function and reduces peripheral immune responses in patients with chronic heart failure. Eur J Cardiovasc Prev Rehabil. 2006 Aug;13(4):592-7. doi: 10.1097/01.hjr.0000219111.02544.ff.

Reference Type: BACKGROUND

PMID: 16874150 (View on PubMed)

Other Identifiers

14-0359

Identifier Type: -

Identifier Source: org_study_id