Effect of Rest Interval Length on the Volume Completed During Upper Body Resistance Exercise

The purpose of the current study was to compare the workout volume (sets x resistance x repetitions per set) completed during two upper body resistance exercise sessions that incorporated 1 minute versus 3 minute rest intervals between sets and exercises. Twelve trained men completed two experimental sessions that consisted of 5 upper body exercises (i.e. barbell bench press, incline barbell bench press, pec deck flye, barbell lying triceps extension, triceps pushdown) performed for three sets with an 8-RM load. The two experimental sessions differed only in the length of the rest interval between sets and exercises; one session with a 1-minute and the other session with a 3-minute rest interval. The results demonstrated that for each exercise, significantly greater workout volume was completed when resting 3 minutes between sets and exercises (p < 0.05). These results indicate that during a resistance exercise session, if sufficient time is available, resting 3 minutes between sets and exercises allows greater workout volume for the upper body exercises examined.

Key points

• The length of the rest interval between sets is an important variable when designing a resistance exercise program and may vary depending on the characteristic being emphasized (i.e. maximal strength, hypertrophy, localized muscular endurance, power).
• Although acknowledged, this variable is rarely monitored precisely in field settings.
• Previous studies that examined rest interval lengths from 1 to 5 minutes between sets for single exercises demonstrated significant differences in repetition performance and the exercise volume completed.
• There is a need for further research to compare the workout volume (sets x resistance x repetitions per set) completed over an entire resistance exercise session with different rest intervals between sets.
• The results of the current study indicate that during a resistance exercise session, if sufficient time is available, resting 3 minutes between sets and exercises allows greater workout volume for the upper body exercises examined.

Key words: Recovery, fatigue, strength, muscle endurance, weight training, strength training     

GLP-1 and Adiponectin: Effect of Weight Loss After Dietary Restriction and Gastric Bypass in Morbidly Obese Patients with Normal and Abnormal Glucose Metabolism

Background  It has been proposed that there is improvement in glucose and insulin metabolism after weight loss in patients who underwent diet restriction and bariatric surgery. Methods  Eleven normal glucose tolerant (NGT) morbidly obese patients [body mass index (BMI), 46.1 ± 2.27 g/m²] and eight abnormal glucose metabolism (AGM) obese patients (BMI, 51.20 kg/m²) were submitted to diet-restriction and bariatric surgery. Prospective study on weight loss changes, over the glucose, insulin metabolism, glucagon-like peptide-1 (GLP-1), and adiponectin levels were evaluated by oral glucose tolerance test during three periods: T1 (first evaluation), T2 (pre-surgery), and T3 (9 months after surgery). Results  Insulin levels improved after surgery. T1 was 131.1 ± 17.60 pmol/l in the NGT group and 197.57 ± 57.94 pmol/l in the AGM group, and T3 was 72.48 ± 3.67 pmol/l in the NGT group and 61.2 ± 9.33 pmol/l in the AGM group. The major reduction was at the first hour of the glucose load as well as fasting levels. At 9 months after surgery (T3), GLP-1 levels at 30 and 60 min had significantly increased in both groups. It was observed that the AGM group had higher levels of GLP-1 at 30 min (34.06 ± 6.18 pmol/l) when compared to the NGT group (22.69 ± 4.04 pmol/l). Homeostasis model assessment of insulin resistance from the NGT and AGM groups had a significant reduction at periods T3 in relation to T1 and T2. Adiponectin levels had increased concentration in both groups before and after surgical weight loss. However, it did not have any statistical difference between periods T1 vs. T2. Conclusions  Weight loss by surgery leads to improvement in the metabolism of carbohydrates in relation to sensitivity to the insulin, contributing to the reduction of type 2 diabetes incidence. This improvement also was expressed by the improvement of the levels of adiponectin and GLP-1.     

Sensitivity and specificity of self‐reported acne in 18‐year‐old adolescent males

Background Self‐reporting is widely used in medical research. The objective of the present study was to evaluate the specificity and sensitivity of self‐reported lesions of acne (scars and active lesions) obtained by an interview with the examination carried out by a dermatologist. Methods A questionnaire was applied to male adolescents who registered for obligatory military service. After that, skin examination was carried out. Results Of the 2,191 adolescents examined, 474 (21.60%) showed acne scars, and 625 (28.51%) admitted to having scars. The sensitivity of self‐reported scars was 50.84%, and the specificity was 77.65%. The prevalence of active acne obtained by the dermatological examination was 85.76% and from self‐reported acne was 76.12%, with a sensitivity of 80.95% and a specificity of 52.88%. Neither schooling nor social class made any difference to sensitivity or specificity. Conclusions Our findings showed that sensitivity and specificity of self‐reported acne was very low, pointing out that, in a sample of adolescents, self‐reporting of acne shows itself as an inadequate instrument for epidemiological studies.     

TINEA VERSICOLOR: HISTOLOGIC AND ULTRASTRUCTURAL INVESTIGATION OF PIGMENTARY CHANGES

A comparative histopathologic study is made between the hypopigmented and hyperpigmented skin lesions of pityriasis versicolor and normal skin areas utilizing histochemical stains and electron microscopy. There were no differences found between the population of Dopa-positive melanocytes within the hypopigmented and hyperpigmented lesions and the normal skin areas. The total epidermal pigmentation was diminished in hypopigmented lesions. The keratin layer was found to be significantly thicker in hyperpigmented lesions and contained more organisms. In hypopigmented lesions, melanocytes contained fewer and smaller melanosomes and exhibited signs of degenerative cellular changes.     

Bone mineral density: Methods of measurement and its influence on primary stability of miniscrews

Objective:To verify whether bone mineral density (BMD) of cortical bone, trabecular bone, and total bone influence the primary stability of orthodontic miniscrews and to verify whether there is a correlation between the measurement of BMD by cone-beam computed tomography (CBCT) and central dual-energy x-ray absorptiometry (DEXA).Materials and Methods:Twenty bovine bone sections were extracted from the pubic and iliac bones from regions with cortical thicknesses of approximately 1 mm. The BMD of the total bone block was evaluated using two methods: CBCT and DEXA. The BMD of cortical, trabecular, and total bone in the region of interest (ROI) were also evaluated by CBCT. After scanning the bone blocks, 20 self-drilling miniscrews (INP®) 1.4 mm in diameter and 6 mm long were inserted into them. The peak implant insertion torque (IT) was registered. After this, the pull-out test (PS) was performed and the maximum force registered. The Pearson correlation test was applied to verify the correlations between variables.Results:The BMD of the total bone block verified by CBCT and DEXA showed a positive and strong correlation (r  =  0.866, P  =  .000). The BMD of the ROI for cortical bone influenced the IT (r  =  0.518, P  =  .40) and the PS of miniscrews (r  =  0.713, P  =  .001, Table 2). However, the total bone BMD (verified by CBCT and DEXA) and trabecular bone BMD presented weak and not statistically significant correlations with primary stability.Conclusions:There was a positive correlation between total bone block BMD measured by DEXA and CBCT. The cortical BMD influenced the IT and PS.     

Human herpesvirus 8 (HHV-8) infection in HIV/AIDS patients from Santos, Brazil: seroprevalence and associated factors

GOAL: The goal of this study was to evaluate the seroprevalence of human herpesvirus 8 (HHV-8) infection among HIV-infected individuals from Brazil and the associated risk factors. STUDY: A cross-sectional survey was carried out with 497 HIV/AIDS outpatients attending the local AIDS Reference Center in Santos (southeastern Brazil) between February 1997 and January 1998 had serum samples screened for anti-HHV-8 antibodies. Patients were considered seropositive whenever reactivity was observed in at least 1 of 3 tests (immunofluorescence assays for latent nuclear and lytic antigens and orf65 recombinant antigen enzyme-linked immunosorbent assay). RESULTS: Overall HHV-8 seroprevalence was 13.9% (95% confidence interval [CI], 10.9-17.6). HHV-8 coinfection was significantly more frequent in men (18.7%; 95% CI, 14.1-23.4) than in women (7.8%; 95% CI, 4.2-11.3) (P < 0.001). According to the mode of HIV acquisition among males, seroprevalence of HHV-8 infection was significantly higher in men who have sex with men when compared with the other groups (32.4% vs. 10.0%, P < 0.001). Multivariate logistic regression revealed HHV-8 infection among men to be independently associated with sexual orientation (adjusted odds ratio [AOR], 5.5 for homosexuals; AOR, 2.8 for bisexuals). No significant risk factor for HHV-8 infection could be demonstrated for HIV-infected women in this cohort, CONCLUSIONS: This study provides further evidence that men who have sex with men are at higher risk of HHV-8 infection and shows that the epidemiologic pattern of this infection among HIV/AIDS patients from Santos, Brazil, is similar to that described in other countries with a low incidence of Kaposi's sarcoma.