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The aim of this study was to examine the effect of adding single-joint (SJ) exercises to a multi-joint (MJ) exercise resistance-training program on upper body muscle size and strength. Twenty-nine untrained young men participated in a 10-week training session. They were randomly divided in 2 groups: the MJ group performed only MJ exercises (lat pulldown and bench press); the MJ+SJ group performed the same MJ exercises plus SJ exercises (lat pulldown, bench press, elbow flexion, and elbow extension). Before and after the training period, the muscle thickness (MT) of the elbow flexors was measured with ultrasound, and peak torque (PT) was measured with an isokinetic dynamometer. There was a significant (p < 0.05) increase in MT (6.5% for MJ and 7.04% for MJ+SJ) and PT (10.40% for MJ and 12.85% for MJ+SJ) in both groups, but there were no between-group differences. Therefore, this study showed that the inclusion of SJ exercises in a MJ exercise training program resulted in no additional benefits in terms of muscle size or strength gains in untrained young men.

Nowadays,a nalytical methods with portable characteristics for on-site and in-situ measurements continue to attract significant attention. In this context,t he use of miniaturizede lectrochemical systems has been proposed because they have severalo ft he requirements of portable methods [1,2].H owever, in manyc ases,m iniaturized systems are characterized by low robustness and reduced range of applications for each system or device. In 1991, Wang and Taha [3] introduced at echnique named batch injection analysis (BIA). In BIA systems with electrochemical detection, as ample plug is injected from am icropipette tip directly on the electrodes urface that is immersed in al arge-volume blank electrolyte solution. Ther esults obtained with aB IA system are conceptionally similar to FIA or SIA, however, withoutu sing additional components such as pumping systems,i njection valves,a nd tubes (possibility of problemsw ith air bubbles and leaks) [4].I nB IA systems, all of these components were replaced by ab attery powered electronic micropipette and, therefore,t he set consisting by BIA cell, electronic micropipette,m ini-potentiostat, and tablet or laptop computerc an be used as ap ortable electrochemical system.R ecently,o ur research group has developed BIA cells specially designed to work with screen-printed electrodes (SPEs) [5,6].S imilar to BIA systems, SPEs also presented some desirable features useful in portable analytical systems,s uch as low cost (large-scale production), disposability,r apid responses,s implicity and robustness (working, countera nd pseudo-reference electrodes are printed on achemically inert substrate).Considering the characteristics of BIA cells and SPEs, one can conclude that the system that combinesb oth de-vices has great potential to be used as ap ortable electrochemical system. Recently,w ei ntroduced ac ompact system composed by aB IA cell specially designed for SPEs( BIASPE cell).F igure 1s howsi mages of the detailed schematic design of the cell (Fig. 1A), photographs of the complete BIASPE cell ( Fig. 1B) and the innovative open-close system (no screws needed) for easy SPE replacement (Fig.1C).When the BIASPE cell is combinedw ith battery-powered accessories( electronic micropipette,p otentiostat and at ablet or al aptop computer), the generateds et can be considered as ar obust portable electrochemical system (Fig.1D). Further details on the proposed BIASPE cell can be found in multiplei mages availablei n supporting information. In addition, specific details on the operation of the BIASPE system (cella ssembly,p ositioning of the SPE in the cell, electronic micropipette operation,a mperometric and voltammetric experiments and visualization of the phenomena that occur on the working electrode surface during injection procedures) can be ac-Abstract:H erein, ac ompact batch injection analysisc ell for screen printed electrodes (BIASPE cell) is reported. Thep roposed system shows several requirements of ap ortable system that include easy-to-operate ("userfriendly"),h igh-speed qu...

The reliability of the lactate threshold (LT) determined in aged rats and its validity to identify an exercise intensity corresponding to the maximal blood lactate steady state (MLSS) were analyzed. Eighteen male aged Wistar rats (approximately 365 days) were submitted to two incremental swimming tests until exhaustion, consisting of an initial load corresponding to 1% of body mass (BM) and increments of 1% BM at each 3-min with blood lactate ([lac]) measurements. The LT was determined by visual inspection (LT(V)) as well by applying a polynomial function on the [lac]/workload ratio (LT(P)) by considering the vertices of the curve. For the MLSS, twelve animals were submitted, on different days, to 3-4 exercise sessions of 30-min with workload corresponding to 4, 5 or 6% BM. The MLSS was considered the highest exercise intensity at which the [lac] variation was not higher than 0.07 mM.min(-1) during the last 20-min. No differences were observed for the test-retest results (4.9 +/- 0.7 and 5.0 +/- 0.8 %BM for LTv; and 6.0 +/- 0.6 and 5.8 +/- 0.6 %BM for LTp) that did not differ from the MLSS (5.4 +/- 0.5 %BM). The LT identified for aged rats in swimming, both by visual inspection and polynomial function, was reliable and did not differ from the MLSS.