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We aimed to compare the effects of beta-alanine on Traditional Resistance Training (TRAD) or Blood Flow Restriction Training (BFR). METHODS: 19 subjects were randomly allocated to a Placebo (n = 10) or beta-alanine (n = 9) group. Subjects from both groups were trained unilaterally (unilateral arm curl) for six weeks, and each arm was trained using a different paradigm (BFR or TRAD). One repetition maximum (1RM) test measurements were performed before and after the strength training program. Work output was accessed as the total weight lifted (repetitions × weight lifted × sets) for the entire strength training program. RESULTS: 1RM or total weight lifted was not increased by beta-alanine supplementation. However, the TRAD-trained arm showed a significantly increased 1RM and total weight lifted compared to the BFR arm (p < 0.05). CONCLUSION: We conclude that in the short-term (6 weeks) and following the current experimental conditions, beta-alanine does not benefit BFR or TRAD in terms of total weight lifted (volume of training) or maximal strength (1RM).

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This study aimed to compare the effects of an 8-week creatine (CR) or placebo (PL) supplementation on muscle strength, thickness, endurance, and body composition employing different training paradigms with blood flow restriction (BFR) vs. traditional resistance training (TRAD). Seventeen healthy males were randomized between the PL (n = 9) and CR (n = 8) groups. Participants were trained unilaterally utilizing a within-between subject bicep curl exercise where each arm was allocated to TRAD or BFR for 8 weeks. Muscular strength, thickness, endurance, and body composition were evaluated. Creatine supplementation promoted increases in muscle thickness in TRAD and BFR compared with their placebo counterparts, however, without a significant difference between treatments (p = 0.349). TRAD training increased maximum strength (1 repetition maximum (1RM)) compared with BFR after 8 weeks of training (p = 0.021). Repetitions to failure at 30% of 1RM were increased in the BFR-CR group compared with the TRAD-CR group (p = 0.004). Repetitions to failure at 70% 1RM were increased from weeks 0-4 (p < 0.05) and 4-8 (p < 0.05) in all groups. Creatine supplementation exerted a hypertrophic effect when utilized with TRAD and BFR paradigms and increased muscle performance at 30% 1RM when utilized in conjunction with BFR. Therefore, creatine supplementation seems to amplify muscle adaptation following a BFR program. Registered in the Brazilian Registry of Clinical Trials (ReBEC), under the registration number: RBR-3vh8zgj.

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Soil profiles from Bavaria in southern Germany and from Chile were analysed for (129)I by accelerator mass spectrometry (AMS), for (127)I by inductively coupled plasma mass spectrometry (ICP-MS), and for (137)Cs by gamma-spectrometry. The mean deposition density of (137)Cs in soils from Bavaria was (41×1.5(±1)) kBq m(-2) (geometric mean and geometric standard deviation), originating mostly from the Chernobyl fall-out. The deposition density of (129)I in these soils was (109×1.5(±1)) mBq m(-2). The dominant sources of (129)I in Bavaria are, however, the reprocessing plants La Hague and Sellafield and not the Chernobyl fall-out. The (129)I/(127)I isotopic ratios of the Bavarian soils were between 10(-7) and 10(-10), i.e. 10(2)-10(5) times higher than the ratios observed for the samples from Chile. The (129)I integral deposition densities in Chile, Easter Island and Antarctica were between 0.3 mBq m(-2) and 2 mBq m(-2). In these soils, the observed (129)I/(127)I ratios were about 10(-12). The soils from Chile allow the determination of the (129)I fall-out from the atmospheric nuclear weapons explosions undisturbed from contaminations due to releases from reprocessing plants. An upper limit of the integral (129)I deposition density of the atmospheric nuclear weapons explosions on the Southern Hemisphere (27°S) is about 1 mBq m(-2). Finally, the dependence of the migration behaviour of (137)Cs, (127)I and of (129)I on the soil properties is discussed. It turns out that there is a distinctly different behaviour of (127)I, (129)I, and (137)Cs in the soils exhibiting different sorption mechanisms for old and recent iodine as well as for (137)Cs.

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The spatial distribution and behaviour of the global fallout (137)Cs in the tropical, subtropical and equatorial soil-plant systems were investigated at several upland sites in Brazil selected according to their climate characteristics, and to the agricultural importance. To determine the (137)Cs deposition density, undisturbed soil profiles were taken from 23 environments situated between the latitudes of 02 degrees N and 30 degrees S. Sampling sites located along to the equator exhibited (137)Cs deposition densities with an average value of 219Bqm(-2). Extremely low deposition densities of 1.3Bqm(-2) were found in the Amazon region. In contrast, the southern part of Brazil, located between latitudes of 20 degrees S and 34 degrees S, exhibited considerably higher deposition densities ranging from 140Bqm(-2) to 1620Bqm(-2). To examine the (137)Cs soil-to-plant transfer in the Brazilian agricultural products, 29 mainly tropical plant species, and corresponding soil samples were collected at 43 sampling locations in nine federal states of Brazil. Values of the (137)Cs concentration factor plant/soil exhibited a large range from 0.020 (beans) to 6.2 (cassava). Samples of some plant species originated from different collecting areas showed different concentration factors. The (137)Cs content of some plants collected was not measurable due to a very low (137)Cs concentration level found in the upper layers of the incremental soils. Globally, the soil-to-plant transfer of (137)Cs can be described by a logarithmic normal distribution with a geometric mean of 0.3 and a geometric standard deviation of 3.9.

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In order to detect characteristic regional differences or temporal changes of 129I concentrations in the biosphere, thyroids from humans, grazing livestock, and herbivorous wildlife species (reindeer and roedeer) were collected in various areas of the world which are not affected by reprocessing plants. For reasons of comparison, all samples were analyzed for their 129I:127I atom ratios. Human and bovine thyroids taken from the 10th region in Southern Chile (39 degrees-41 degrees South) indicated values of the 129I:127I atom ratio between 1.1 x 10(-9) and 2.0 x 10(-9) and between 1.2 x 10(-10) and 9 x 10(-9), respectively. They showed no significant increase in the concentration of biospheric 129I in comparison with that established in the pre-nuclear age. Atom ratios found in human thyroids collected in Lower Saxony (Federal Republic of Germany), which is a region not directly affected by reprocessing plants, exhibited 129I:127I values between 8 x 10(-9) and 6 x 10(-8) from February 1988 to September 1990. Thyroid glands of reindeer and roedeer as well as heather, moss, and lichen were taken from the Vilhelmina, Heby, and Gävle communes in Sweden and analyzed for 129I and 127I. All three communes were found to be seriously contaminated by fallout from the Chernobyl accident. Highest 129I:127I atom ratios between 3.5 x 10(-7) and 1 x 10(-6) were found in the Gävle commune (approximately 150 km northwest of Stockholm) where the highest 137Cs ground deposition (70-80 kBq m-2) was measured. Two soil samples taken from Krasnaya Gora and Mirny locations in Russia (approximately 200 km northeast of Chernobyl) exhibited ratios of about 1 x 10(-6). These locations showed a 137Cs ground deposition of 370 and 1,300 kBq m-2, respectively.

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