Weight loss improves neurovascular and muscle metaboreflex control in obesity.
We studied the effects of a hypocaloric diet (D, n = 24, age: 32.2 +/- 1.4 yr, body mass index: 34.7 +/- 0.5 kg/m2) and a hypocaloric diet associated with exercise training (D + T, n = 25, age: 32.3 +/- 1.3 yr, body mass index: 32.9 +/- 0.4 kg/m2) on muscle metaboreflex control, muscle sympathetic nerve activity (MSNA, microneurography), blood pressure, and forearm blood flow (plethysmography) levels during handgrip exercise at 10% and 30% of maximal voluntary contraction in normotensive obese women. An additional 10 women matched by age and body mass index were studied as a nonadherent group. D or D + T significantly decreased body mass index. D or D + T significantly decreased resting MSNA (bursts/100 heartbeats). The absolute levels of MSNA were significantly lower throughout 10% and 30% exercise after D or D + T, although no change was found in the magnitude of response of MSNA. D + T, but not D, significantly increased resting forearm vascular conductance. D + T significantly increased the magnitude of the response of forearm vascular conductance during 30% exercise. D or D + T significantly increased MSNA levels during posthandgrip circulatory arrest when muscle metaboreflex is isolated. In conclusion, weight loss improves muscle metaboreflex control in obese women. Weight loss reduces MSNA, which seems to be centrally mediated. Weight loss by D + T increases forearm vascular conductance at rest and during exercise in obese individuals.
Trombetta
Ivani Credidio
IC
Instituto do Coração-(InCor), Unidade de Reabilitação Cardiovascular e Fisiologia do Exercício, Av. Dr. Enéas de Carvalho Aguiar 44, Cerqueira César, São Paulo, SP CEP 05403-000, Brazil.
Batalha
Luciana T
LT
Rondon
Maria Urbana P B
MU
Laterza
Mateus Camaroti
MC
Kuniyoshi
Fatima H S
FH
Gowdak
Márcia M G
MM
Barretto
Antonio Carlos P
AC
Halpern
Alfredo
A
Villares
Sandra M F
SM
Negrão
Carlos Eduardo
CE
D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D001808:Blood Vessels / Q000294:innervation / Q000502:physiology; D002149:Energy Intake / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005260:Female; D005542:Forearm / Q000098:blood supply; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000098:blood supply*; D009765:Obesity / Q000178:diet therapy / Q000503:physiopathology*; D010991:Plethysmography; D012018:Reflex / Q000502:physiology*; D013564:Sympathetic Nervous System / Q000502:physiology*; D015431:Weight Loss / Q000502:physiology*