Body composition assessment in a large cohort of Olympic athletes with different training loads: possible reference values for fat mass and fat-free mass domains

AIMS

To assess body composition by means of BOD POD in the large cohort of Italian Olympic athletes of many sport disciplines (studied at the same time), and to provide possible reference values for body composition in elite athletes.

METHODS

1556 elite athletes, who took part in the selection procedure for the 2016 Rio Olympic Games for the National Italian Olympic Committee (CONI), were retrospectively studied. Body composition was determined using air plethysmography-based BOD POD.

RESULTS

We observed that Fat Mass (FM) and Fat-free Mass (FFM) should be considered as two mutually independent domains in elite athletes. By performing Principal Component Analysis, we defined two independent main domains (respectively, representing FM and FFM), which presented different trends according to gender and static or dynamic exercise load. Lastly, we reported possible reference values for FM index and FFM index, respectively, representing the largest contributors to FM domain and FFM domain, and calculated as FM or FFM (kg)/height (m2).

CONCLUSIONS

Our findings might provide a basis to optimize the practical approach to body composition in athletes, highlighting the importance of considering indicators of fat mass and lean mass "simultaneously" and not specularly, according to different sport disciplines as well. Moreover, these data might contribute to standardize reference values for body composition in elite athletes, with a view to potentially helping to monitor and guide training regimens, prevent related detrimental practices and plan cardiometabolic prevention and rehabilitation programs.

Physical Activity Is Associated with Attention Capacity in Adolescents

OBJECTIVE

To assess the relationships among physical activity, measured objectively, and attention capacity in European adolescents.

STUDY DESIGN

The study included 273 adolescents, aged 12.5-17.5 years, who participated in the Healthy Lifestyle in Europe by Nutrition in Adolescence Study. Participants wore a uniaxial accelerometer for 7 days to measure physical activity. The d2 Test of Attention was administered to assess attention capacity. Multivariate analyses were used to study the association of attention capacity with each measure of physical activity. Receiver operating characteristic analysis was performed to determine thresholds that best discriminate between low and good attention capacity.

RESULTS

After controlling for potential confounding variables (age, sex, body mass index, parental educational level, fat mass, aerobic fitness, and center), adolescents' attention capacity test performances were significantly and positively associated with longer time spent in moderate or moderate-to-vigorous physical activity (MVPA) in free-living conditions (P < .05). Receiver operating characteristic curve analyses revealed that the physical activity thresholds that best discriminated between low/good attention capacities were ≥41 min·day(-1) for moderate, ≥12 min·day(-1) for vigorous, and ≥58 min·day(-1) for MVPA.

CONCLUSION

These findings suggest that promoting MVPA may be have a beneficial effect on attention capacity, an important component of cognition, in adolescents.

Homocysteine predicts increased NT-pro-BNP through impaired fatty acid oxidation

BACKGROUND

The deficiency in methyl donors, folate and vitamin B12, increases homocysteine and produces myocardium hypertrophy with impaired mitochondrial fatty acid oxidation and increased BNP, through hypomethylation of peroxisome-proliferator-activated-receptor gamma co-activator-1α, in rat. This may help to understand better the elusive link previously reported between hyperhomocysteinemia and BNP, in human. We investigated therefore the influence of methyl donors on heart mitochondrial fatty acid oxidation and brain natriuretic peptide, in two contrasted populations.

METHODS

Biomarkers of heart disease, of one carbon metabolism and of mitochondrial fatty acid oxidation were assessed in 1020 subjects, including patients undergoing coronarography and ambulatory elderly subjects from OASI cohort.

RESULTS

Folate deficit was more frequent in the coronarography population than in the elderly ambulatory volunteers and produced a higher concentration of homocysteine (19.3 ± 6.8 vs. 15.3 ± 5.6, P<0.001). Subjects with homocysteine in the upper quartile (≥ 18 μmol/L) had higher concentrations of NT-pro-BNP (or BNP in ambulatory subjects) and of short chain-, medium chain-, and long chain-acylcarnitines, compared to those in the lower quartile (≤ 12 μmol/L), in both populations (P<0.001). Homocysteine and NT-pro-BNP were positively correlated with short chain-, medium chain-, long chain-acylcarnitines and with acylcarnitine ratios indicative of decreased mitochondrial acyldehydrogenase activities (P<0.001). In multivariate analysis, homocysteine and long chain acylcarnitines were two interacting determinants of NT-pro-BNP, in addition to left ventricular ejection fraction, body mass index, creatinine and folate.

CONCLUSIONS

This study showed that homocysteine predicts increased NT-pro-BNP (or BNP) through a link with impaired mitochondrial fatty oxidation, in two contrasted populations.

Lack of correlation between ventricular late potentials and left ventricular mass in top-level male athletes

PURPOSE

The aim of this study was to establish: 1) the prevalence of abnormal signal-averaged electrocardiogram (SAECG) in a large population of top-level athletes and 2) the relationship between SAECG parameters and left ventricular mass. One-hundred and fifty-three elite male athletes without apparent heart disease, symptoms, or arrhythmias were studied.

METHODS

Fifty-six athletes (37%) had increased left ventricular mass (> 134 g.m(-2)). All athletes underwent time-domain SAECG on 300-400 heart beats recorded at rest from three bipolar orthogonal tests with a filter setting of 40-250 Hz. Criteria for abnormality were 1) filtered QRS duration > 114 ms, 2) duration of low-amplitude signals > 38 ms, or 3) root mean square voltage of the last 40 ms of the filtered QRS < 20 microV.

RESULTS

The prevalence of abnormal SAECG was 7.2% (abnormality of one parameter), 6.5% (abnormality of two parameters), and 5.8%(abnormality of three parameters). The prevalence of abnormal SAECG was similar in athletes with or without increased left ventricular mass.

CONCLUSIONS

In conclusion, this study showed: 1) the low rate of positive results of SAECG parameters in top-level male athletes, similar to that found in healthy sedentary subjects; and 2) the lack of correlation between left ventricular mass and overall SAECG parameters.

Scalp topographic mapping of middle-latency somatosensory evoked potentials in normal aging and dementia

Middle-latency somatosensory evoked potentials (MLSEPs) were recorded in four groups of subjects: 13 normal young controls (mean age, 17.9 years). 11 normal elderly (mean age, 66.9 years), 11 patients with dementia of Alzheimer's type (DAT: mean age, 70.5), and four with vascular dementia (mean age, 79.3). MLSEPs in normal elderly showed an increase in the latency of P22, N30, P45, N60, and P100, and in the amplitude of N60. DAT patients also presented such changes; however, the increase in the amplitude of N60 was much more evident than that found in normal aging and was accompanied by a significant increase in amplitude of P45. Patients with vascular dementia tended to show longer latencies and larger amplitudes than the other groups. The increase in amplitude of P45 and N60 in MLSEPs seems to be characteristically associated with normal aging and the development of dementia. It is suggested that the mechanism of such functional changes might be correlated with the structural and neurochemical changes accompanying neuronal loss in these conditions.