Moran Saghiv

The effects of aerobic and anaerobic exercises on circulating soluble-Klotho and IGF-I in young and elderly adults and in CAD patients

Different studies support the notion that chronic aerobic exercises training can influence the circulating levels of soluble-Klotho (s-Klotho) and insulin-like growth factor 1 (IGF-I). The effects of s-Klotho include improving the quality of life, alleviating the negative impact of age on the body’s work capacity, and possibly increasing longevity. This review provides an overview of the latest findings in this field of research in humans. The different modes of dynamic exercise and their impact on circulating levels of s-Klotho and IGF-I in young adult athletes, untrained young adults, trained healthy older adults, untrained healthy older adults, and coronary artery disease (CAD) patients are reviewed and discussed. Together these findings suggest that long-lasting (chronic) aerobic exercise training is probably one of the antiaging factors that counteract the aging and CAD process by increasing the circulating s-Klotho and lowering the IGF-I levels. However, following anaerobic exercise training the opposite occurs. The exact metabolic and physiological pathways involved in the activity of these well-trained young and master sportsmen should be further studied and elucidated. The purpose of this review was to provide a clarification regarding the roles of s-Klotho and intensities and durations of different exercise on human health.

Aerobic Training Effect on Blood S-Klotho Levels in Coronary Artery Disease Patients

Rationale: Aerobic exercise and Klotho gene expression reduce the risk of cardiovascular events in patients with prior coronary artery disease (CAD) thus, aerobic exercise may create a decreased risk of mortality. Objective: The purpose of the present study was to compare the association between s-klotho serum levels and IGF-1 levels in 3 groups: 60 untrained coronary artery disease patients (CAD) age 52.6 ± 2 years, 60 active participants with CAD in supervised aerobic programs for at least 12 months (4-5 times•wk-1) age 53.0 ± 2 years, and 40 untrained healthy males, age 53.6 ± 1.5 years to assess association of aerobic training and s-klotho activity. Methods and results: Blood samples were drawn from a forearm vein after overnight fasting, s-Klotho levels in the serum were analyzed using an α-klotho Enzyme Linked Immunosorbent Assay ELISA kit, while, IGF-1 was measured by a chemiluminescent immunometric method. Significant (p>0.05) differences were noted between the aerobically trained CAD patients and both untrained groups: CAD patients and healthy subjects with regard to s- Klotho (491 ± 66, 386 ± 70 and 418 ± 81 pg•mL-1 respectively), IGF-1 (82 ± 12, 106 ± 21 and 98 ± 14 nmol•L-1 respectively) and maximal oxygen uptake (42.1 ± 4.5, 31.9 ± 3.9 and 35.8 ± 2.9 mL•kg-1•min-1 respectively). Conclusions: S-Klotho and aerobic exercise training are factors that may promote upgrading capacities of the CAD patients. Inflection of Klotho expression through aerobic training represents a relationship that may contribute to the explanation of the effects of aerobic activity on CAD patients. In addition, findings suggest that atenolol treatment does not influence s-Klotho and IGF-1 levels in CAD patients treated with atenolol.

Energy Sources at Peak All-out Exercise in Adolescents and Young Adults

Purpose: To examine the aerobic energy portion utilized during the Wingate Anaerobic Test. Methods: Power output was compared with direct values obtained from measured oxygen uptake (VO2), in 14 (14.4 ± 1.0 yrs) healthy adolescents and 14 young adults (26.0 ± 1.0 yrs). Results: All subjects completed the exercise challenges without ECG abnormality. At rest, significant (P<0.05) differences were noted between the groups in heart rate, and diastolic blood pressure. At peak exercise, significant (P<0.05) differences were noted between adolescents and young subjects for oxygen uptake (21.5 ± 0.3 vs. 18.3 ± 0.3 mLO2 × kg-1 × min-1 respectively), power output for 30 s (0.63 ± 0.3 vs. 0.78 ± 0.3 LO2 × min-1/2 respectively), aerobic energy portion utilized (40.7 ± 4.7 vs. 17.7 ± 3.2 % respectively) and lactic acid (8.5 ± 0.7 and 12.6 ± 1.1 mmol × L-1 respectively). In addition, differences were seen in heart rate, systolic blood pressure, diastolic blood pressure, and mean arterial blood pressure. Conclusions: The results reflect a significant noticeably lower anaerobic power output during adolescence, which suggests that glycolytic activity is age-dependent. This may be related to different muscle substrate, enzyme activity and differences in phosphorus compounds between fast and slow fiber types. As a result, adolescents relied more on oxidative metabolism compared to young adults.

Beta-blockers and aerobic training on peripheral adrenoceptor numbers in CAD patients

Purpose: Aerobic training and beta blockers may manipulate adrenoceptors number. Therefore, the present study examined the effect of aerobic exercise training on the adrenoceptors number in coronary artery disease patients (CAD) treated with atenolol β-blocker. Methods: Sixty patients: 30 males and 30 women with diagnosed CAD were treated for twelve weeks with atenolol β-blocker. Following the 12 weeks atenolol treatment, patients were divided randomly into four groups: 15 males aged (years) 46.6±2.0 (MTR) and 15 trained females47.3±2.0 (FTR) were assigned for 12 weeks aerobically in addition to the atenolol while, 15 males46.8±2.0 (MC) and 15 women46.9±2.0 (FC) treated only with atenolol served as controls. Adrenoceptors were measured by the specific binding 3H-CGP 12177. Results: Following atenolol treatment, all groups significantly (p<0.05) reduced adrenoceptor levels (MTR 3.50±0.17 to 3.07±0.19, FTR 3.42±0.16 to 3.09±0.15, MC 3.49±0.14 to 3.07±0.19 and FC 3.44±0.15 to 3.05±0.14 fmol/106). Following aerobic training, levels of adrenoceptors rose significantly (p<0.05) in the MTR from 3.07±0.19 to 3.74 ±0.14, and FTR from 3.09±0.15 to 3.69±0.16 whereas in the MC and FC groups it remained unchanged (3.07±0.19 and 3.05 fmol/106 respectively). Conclusions: Data suggest that in males and females regular and habitual moderate intensity aerobic exercise combined with atenolol β-blocker treatment may help to counter the β-blocker related decline in the β-adrenergic receptors number.

Are there Differences between Adolescent Males and Females forMaintaining the Metabolic Cost at Maximal Oxygen Uptake

Purpose: The present study looked at gender difference in oxygen delivery-extraction at maximal oxygen uptake in healthy adolescents. Methods: 36 adolescent males (14.9 ± 1.1 years) and 33 adolescent females (15.0 ± 1.1 years) underwent a maximal oxygen uptake test and a two dimensional direct m-mode echocardiography performed on a bicycle ergometry. Arteriovenous oxygen difference was defined by utilizing the Fick equation. Results: At rest, males compared to females had significantly (p<0.05) higher oxygen extraction (38.8 ± 1.4 and 31.8 ± 1.2 mL.kg-1 .min-1 respectively), systolic blood pressure, and mean arterial blood pressure. At peak exercise test, males compared to females demonstrated significant (P<0.05) higher values for cardiac output (16.6 ± 0.7 and 15.4 ± 0.6 L∙min-1 respectively), stroke volume (83.9 ± 5.1 and 78.5 ± 4.6 mL respectively), oxygen uptake (47.3 ± 3.7 and 39.6 ± 1.1 mL∙kg-1∙min-1, respectivel y), while oxygen extraction was significantly higher in females compared to males (123.6 ± 7.6 and 115.5 ± 5.4 mL∙L-1 respectively). Conclusions: This study suggests that normal adolescents; male and females respond to the maximal oxygen uptake test by increased their left ventricular systolic function, however, it was less augmented in the females due to gender and energy metabolism differences. Consequently, females increased their oxygen extraction more than the males as a compensation for the lower cardiac output and hence, lower oxygen delivery.

What Maintains the Metabolic Cost at Peak Aerobic Exercise in End StageRenal Disease Patients

Background: End-stage renal disease (ESRD) reduces performance of cardiopulmonary function and peak oxygen uptake (VO2 peak). The possible roles of oxygen delivery and oxygen extraction as limiting factors of exercise tolerance in ESRD patients were assessed.Methods: A cross-sectional study was conducted with twenty-two ESRD patients who underwent a peak cardiopulmonary and echocardiograph exercise test via leg cycle ergometry.Results: During exercise, elevated lactic acid occurred at a mean workload of 68.6 ± 5.7 Watts, corresponding to 78% of their respective peak work capacity. At peak exercise, in all measured variables except for systolic blood pressure, ESRD patients did not achieve normally predicted values. Heart rate, left ventricular end diastolic and systolic volumes, stroke volume, cardiac output, VO2 peak, arteriovenous oxygen difference, and workload were below normal values, while diastolic blood pressure, mean blood pressure and total peripheral resistance were above normal values.Conclusions: In ESRD patients, values for both oxygen delivery and extraction were far below the recorded values in normal. This suggests diminished central cardiopulmonary responses as well as reduced peripheral capacity to extract oxygen at the muscle level. Findings support the concept and possible importance of exercise rehabilitation programs in the approach for treatment of ESRD patients.

NTproBNP, Lactate, and Hemodynamic Responses to Multiple vs One-Repetition Max Strength Tests

Background: Cardiac stress biomarker N-Terminal pro-brain natriuretic peptide (NTproBNP), blood lactate, and hemodynamic responses were compared between one-repetition max (1RM) and multiple-repetition max (MRM) strength assessments in overweight and obese conditions. Methods: Twenty sedentary males, ages 19–28 years, were divided into overweight (n = 11) and obese (n = 9) groups. Subjects performed MRM and 1RM using a chest press machine. Heart rate (HR), blood pressure, blood lactate, and NTproBNP were measured at baseline, immediately post, and 15-min post strength assessment. Power output was also calculated. Results: Significant increases in all variables except NTproBNP were observed from baseline to immediate post (p < 0.05) in both 1RM and MRM. Significant differences in HR were found between 1RM and MRM immediate post (1RM = 122 bpm, MRM = 147 bpm; p = 0.001), and blood lactate immediate post (1RM = 3.0 mmol·L−1, MRM = 5.7 mmol·L−1; p = 0.001) and 15-min post (1RM = 1.9 mmol·L−1, MRM = 4.mmol·L−1...

Long Lasting Chronic Resistive Training Effects on Circulating S-Klotho and IGF-1

Purpose: The purpose of the present study was to examine the effects of long lasting chronic resistive training on circulating s-klotho s and IGF-1 levels in young adult. Methods: 50 national level powerlifters and 50 age matched untrained young adults (27.1±1.0 and 26.5±1.0 years respectively). Following overnight fasting forearm vein blood samples were taken, circulating s- Klotho were examined by means of a-klotho Enzyme Linked Immunosorbent Assay ELISA kit. A chemiluminescent immunometric method was applied in order to define serum IGF-1 levels. Results: No significant differences were seen between the weightlifters and untrained young adults for s-Klotho (421.0±76.0 and 435.2 ±89.0 pg·mL-1 respectively). However, IGF-1 levels were significantly (p<0.05) higher in the weightlifters compared to the untrained subjects (110.6±16.4 and 77.6±23.2 mmol·L-1 respectively). Conclusions: It seems that long lasting resistive training did not influence circulating levels of s-Klotho, while the increased circulating IGF-I may, at least in part, mediate increases in strength, power and muscle hypertrophy.