Mechanical and metabolic responses during a high-intensity circuit training workout in competitive runners.

AIM: This study aimed to assess the mechanical and metabolic responses of competitive runners throughout a high-intensity circuit training (HICT) workout, designed to improve explosive strength under acute metabolic fatigue. METHODS: Eight high-level endurance runners (age: 21.8±3.7 y; body mass: 61.5±5.7 kg; height: 175.2±5.2 cm; 1500-m record: 3 min 54±7 s) completed an incremental exhaustive running test to determine the maximum oxygen uptake (VO2max) and maximum aerobic speed (MAS). The athletes then performed on a track a HICT workout, consisting of two identical circuits interspersed by 5-min of passive recovery. Each circuit was constituted by six 30-s dynamic or explosive strength exercises, alternated to 200-m runs (1000-m for the final run) at 90-95% of MAS. During a hopping exercise included in the circuit, and during the 1000-m run, lower limb stiffness measures were obtained from contact and flight times using a method based on the spring-mass model. RESULTS: Hopping stiffness was significantly lower (P<0.05) in the second circuit (12.42±2.70 kN·m⁻¹) compared to the first one (13.76±2.10 kN·m⁻¹). Conversely, leg stiffness during running was similar (P>0.05) in the first and the second circuit (8.08±1.49 vs. 7.87±1.31 kN·m⁻¹), as well as vertical stiffness (33.56±5.25 vs. 32.16±5.45 kN·m⁻¹). The mean VO2 in the 1000-m run of the two circuits was 93.17±3.56% and 93.47±3.91% of VO2max, respectively. CONCLUSION: Despite the occurrence of acute neuromuscular fatigue throughout the workout, the runners avoided an impairment of their stiffness during running. Furthermore, the relatively high percentage of VO2max achieved indicates the HICT involves also stimuli for aerobic conditioning.

Exercise training in mild hypertension: effects on blood pressure, left ventricular mass and coagulation factor VII and fibrinogen.

The aim of this study was to assess the effects of aerobic exercise on resting and 24-hour blood pressure (BP), left ventricular mass (LVM), plasma fibrinogen and factor VII (FVII). For this purpose 14 sedentary subjects with untreated diastolic BP between 90 and 104 mm Hg completed a 12-week supervised exercise program. At the end of this period, 8 subjects resumed a sedentary life-style and were reexamined 2 months later (detraining). Baseline, posttraining and postdetraining examinations included resting BP assessment, ambulatory BP monitoring, cardiopulmonary stress test, echocardiography and measurements of plasma fibrinogen and FVII. Exercise-mediated increase in aerobic fitness (VO2 max + 24%) was associated with a significant reduction in resting systolic and diastolic BP (p < 0.01), mean systolic and diastolic 24-hour BP (p < 0.001) and LVM index. As for the coagulation parameters only the concentration of fibrinogen significantly decreased (p < 0.01) whereas FVII remained unchanged. The 8 subjects that resumed a sedentary life-style were reexamined 2 months later: their resting BP, 24-hour BP and fibrinogen concentration returned to baseline values; only the effect on LVM was conserved. Our study underlines the usefulness and safety of regular physical exercise in mild hypertension. Most of the patients (11 of 14) had their BP normalized and a significant reduction in LVM and fibrinogen concentration was observed, leading to an overall improvement in coronary risk profile.

[The effects of chronic cilazapril treatment on sympathetic vasomotor tonus: a spectral analysis study of pressure variability]. / Effetti del trattamento cronico con cilazapril sul tono vasomotorio simpatico: studio con analisi spettrale della variabilità pressoria.

Animal experiments suggest that an important component of the antihypertensive effects of ACE inhibitors might derive from an inhibition of the sympathetic vasomotor tone. We addressed this problem on 22 mildly hypertensive subjects (48 +/- 2 years; arterial pressure 151 +/- 3/95 +/- 1 mmHg), in whom sympathetic vasomotor tone was non invasively inferred by the power of the low frequency component (0.1 Hz) of the spontaneous oscillations of systolic arterial pressure (LFSAP), during placebo and after 4 weeks of treatment with a new ACE inhibitor, cilazapril, 5 mg per os oid. LFSAP was computed at rest and during physical (active orthostatism) and mental (computerized attentional test and mental arithmetic) stimuli capable of enhancing sympathetic drive. Cilazapril treatment reduced resting arterial pressure to 128 +/- 3/80 +/- 2 mmHg, without affecting heart rate (78 +/- 2 and 74 +/- 2 b/min, respectively). The increases in LFSAP produced by standing were significantly greater during placebo than during active treatment (delta LFSAP = 10 +/- 3 and 5 +/- 2 mmHg2, respectively). These data suggest that an important reduction of sympathetic vasomotor tone accompanies the antihypertensive effects of chronic ACE-inhibitor treatment.

Effects of chronic cilazapril treatment on cardiovascular control: a spectral analytical approach.

In 11 subjects with mild hypertension (sitting arterial pressure of 146 +/- 5/97 +/- 2 mm Hg), the effects of chronic angiotensin-converting enzyme (ACE) inhibition (cilazapril, 5 mg p.o. once daily for 4 weeks) were studied at rest and during active standing by means of spectral analysis. Sympathetic vascular control was inferred from the power of the low-frequency (LF) component of the systolic arterial pressure (SAP) variability, assessed noninvasively with a plethysmographic technique. Simultaneously, quantitative indices of neural control of the sinoatrial (SA) node were obtained with the power of the LF and of the high-frequency (respiration linked) component of R-R variability. Before treatment, active standing produced a clear increase in the LF components of R-R and SAP variabilities. At the end of the 4 weeks of cilazapril treatment, the LF component of SAP variability during standing was significantly lower than prior to treatment, while the increase in the LF component of R-R variability was left unchanged. These findings suggest an inhibitory effect of chronic ACE inhibition upon vasomotor sympathetic control, as assessed non-invasively by this technique.

[Arterial hypertension in perimenopausal women; tolerability of etozolin]. / Ipertensione arteriosa in donne in età perimenopausale; indagine di tollerabilità dell'etozolina.

Twenty women aged 45-55 years with mild-moderate hypertension were treated for 12 months with etozolin, a new loop diuretic. All patients concluded the study; resting systolic pressure was reduced from 164 +/- 3 to 145 +/- 3 mmHg; diastolic blood pressure dropped from 103 +/- 2 mmHg to 90 +/- 1 mmHg. No changes of blood glucose, blood nitrogen, serum Na+, K+, creatinine, cholesterol, triglycerides were observed, nor serious adverse reaction appeared. In conclusion, etozolin is a safe and effective antihypertensive agent in a selection of hypertensive patients highly sensitive to pharmacological side effects.

[Methods of determination of stroke volume from M-mode echocardiogram of the aortic valve and aortic root. A comparative evaluation]. / Metodi di determinazione della gettata sistolica dall'ecocardiogramma M-mode della valvola aortica e della radice aortica. Una valutazione comparativa applicata.

The purpose of this study is to evaluate four methods of determining left ventricular stroke volume (SV) from aortic valve (AV) and aortic root (AR) M-mode echocardiogram (Table I, formulas 1-4); secondly, to study relations between echocardiographic aortic variables and SV. We studied 20 patients (Pts) in our Coronary Unit, 14 men and 6 women; their ages ranged from 38 to 76 (mean 53.4) years. Seventeen Pts had acute myocardial infarction; two Pts had previous myocardial infarction and heart failure; one Pt had dilated cardiomyopathy and heart failure. Three out of the twenty Pts, had mitral insufficiency (Table II, clinical and hemodynamic data). Patients were studied with high quality M-mode echocardiography. Immediately after the examination repeated measurements of cardiac output by thermodilution technique (TD) were carried out, and values of SV calculated (SV-TD). Twenty-five complete procedures were accomplished. The formulas were applied to every patient's echocardiographic data, and results (SV-ECHO) compared with SV-TD (Table III). Echocardiographic variables, whether single or multiple (terms), were also studied with regard to their relation with SV-TD (Table IV). Mean +/- SD value of SV-TD of the study group was 60.3 +/- 24.7 ml; range 22.7 to 108 ml. Mean +/- SD values of SV-ECHO were as follows: Yeh's formula, based on squared mean AV opening and LVET, 56 +/- 22.6 (ml), r = 0.8278, SEE 12.98; Jacobs' formula, based on aortic box planimetry, 68 +/- 32.5 (ml), r = 0.7129, SEE 23.31.(ABSTRACT TRUNCATED AT 250 WORDS)

[Altered diastolic function of the left ventricle in juvenile diabetes. Computerized echocardiographic study]. / Alterata funzione diastolica ventricolare sinistra nel diabete giovanile. Studio ecocardiografico computerizzato.

Using digitized M-mode ecocardiography, 26 young subjects with type I diabetes mellitus of at least three years duration, without any clinical evidence of heart disease have been studied, searching for subclinical impairment of left ventricular function. Patients have been divided in two groups according to the presence (Group I, N degrees 7 patients) or absence (Group II, N degrees 19 patients) of retinopathy. The time interval from the shortest left ventricular diameter to the onset of mitral valve opening was significantly increased as compared with the control Group (10.20 +/- 8.88 control Group; 29.21 +/- 12.99 Group II, p less than 0.001; 41.00 +/- 12.29 Group I, p less than 0.001). Furthermore, a close correlation between the above named time interval and the duration of diabetes was found (r = 0.496, p less than 0.01). Finally, the change of left ventricular dimension during the time interval from the shortest left ventricular diameter to the onset of mitral valve opening, expressed as a percentage of left ventricular end-diastolic diameter, was increased (3.20 +/- 3.43 control Group; 8.21 +/- 5.51 Group II, p less than 0.02; 12.43 +/- 5.56 Group I, p less than 0.001). Our results suggest an impairment of ventricular relaxation due to increased wall stiffness. We conclude that there are often subclinical cardiac abnormalities in young diabetics resulting in impairment of diastolic function that is correlate with the duration of diabetes and with the presence of clinical complications such as retinopathy.

[Acromegalic cardiomyopathy: an echocardiographic study]. / La cardiomiopatia acromegalica: studio ecocardiografico.

Thirty eight acromegalic patients (A) and a control group (C) of subjects without heart disease, were studied with echocardiography. Acromegalies were divided in two groups, A1 and A2, who had increase or normal serum growth hormone (GH) levels respectively after treatment (pituitary adenectomy and/or bromocriptine), at the time of the study. In acromegalic patients (A) mean left ventricular (LV) dimensions were normal while LV wall and septal thickness, LV mass and left atrial (LA) dimension were increased compared to control subjects. LVH was present in 79% of acromegalic patients. Asymmetric septal hypertrophy (ASH) was found in 10,5% of our patients. In group A1, IVS, LVPW, LVMM/m2 were significantly increased as compared to group A2. Fractional shortening (FS), ejection fraction (EF), mean velocity of circumferential fibre shortening (Vcf), frequency-normalized Vcf (Vcfn), posterior left ventricular wall velocity (PWV), and normalized PWV (PWVn) were normal in both groups. In patients with active acromegaly (Al) IVS and LVMM/m2 correlated well with the total duration of the disease (r=0.550 p less than 0.01 for IVS; r=0.624 p less than 0.01 for LVMM/m2) and with the duration of acromegaly before treatment (r=0.568, p less than 0.01 for IVS; r=0.500 p less than 0.01 for LVMM/m2). Furthermore a positive correlation was found between IVS and GH levels (r=0,550 p less than 0.01). Concomitant coronary artery disease and or hypertension did not seem to play any role in causing the above mentioned echocardiographic changes. Echocardiography is useful in assessing the cardiac involvement in patients with acromegaly.

[On the splitting of the second sound in early infancy (author's transl)]. / Sullo sdoppiamento del secondo tono nelle prime settimane di vita.

The increase of the A2-P2 interval and the linear correlation between the increase of this interval and the decrease of the ratio right: left ventricular forces on the ratio right: left ventricular forces on the ECG is in accordance with recent explanation of the mechanism of the second sound. The asynchronism between the two components of the second sound should be due to the difference in resistance and capacity of the two circulations that takes place in the first month of life.