Similarly, the best type of recorder to use is determined by its ability to capture the sounds of interest with the necessary temporal and frequency resolution. Manufacturers' performance specifications are a starting point, although these may often be optimistic, subject to change with age of the machinery and may differ between individual recorders of the same model (particularly analogue tape recorders). It is therefore advisable to include a calibration sound of known frequency and duration at the beginning of a recording session. Digital recorders (solid-state or DAT) are limited by the sampling rate of their analogue to digital converters, so special care is necessary when recording high frequency sounds. Increasingly, field recordings are being made with devices using data compression to increase storage capacity (e.g. MiniDisc). The data compression algorithms remove parts of the signal that are not perceptible to humans, but they can also remove or distort important biological signal components [57].
Same Time Same Place Peake Pdf Download
The census strategy used for corncrakes was developed from radio-tagging studies [41], which found that males rarely move more than 250 m between nights and that on any particular night around 75% of males would call. Based on these findings, censuses were carried out on two nights and if two calling locations were within 250 m of each other on both nights, they were judged to come from the same individual [41]. Corncrakes have individually distinctive vocalizations [13, 112], which are consistent over years [13]. The census rules present obvious sources of bias and Peake & McGregor [40] monitored corncrakes using vocal individuality to show that males called far less than anticipated (41% of males per night) and this led to the population being underestimated by up to 30%. They were also able to follow individuals throughout the season and showed that habitat quality affected movement, with males in poor quality habitat moving greater distances. Their study also shows that tracking movements using the standard census approach was in most cases accurate [40]. The main role for vocal individuality in this case would be to provide correction factors to refine standard census rules or as a method for monitoring individual movements in relation to small-scale habitat differences.
The most effective test of vocal individuality will be through simulated census and monitoring situations [81, 98]. These can be achieved through blind trials and repeated random sampling from known data sets to create population samples of unknown size and composition. We tested the use of neural network models in census and monitoring tasks by using a data set of 30 individuals that was randomly sampled [98]. The same individual could appear several times, and we used neural networks to classify individuals in a series of blind trials. These kinds of test more accurately simulate how the technique will perform as a conservation tool.
In most cases the people developing and testing monitoring techniques are not the same as those who will be using them in the field. Thus, one important, if obvious, point is that specific guidelines need to be given to those who will collect and analyse recordings. For many endangered or low-density populations, collecting recordings requires considerable fieldwork (e.g. [53]), and therefore this warrants the most efficient (effort vs. results) analysis possible. It may not be possible to rely on spontaneous vocalizing to collect enough recordings and playback is often used to elicit calls. However, the time of playback or its overuse can also have biasing effects, for example by causing individuals to move off their territories [37, 38].
A number of exercise training studies (e.g., 5-10 weeks) incorporating creatine supplementation have shown no increases in total body water (TBW). For example, resistance-trained males who received creatine at a dose of 0.3 g/kg lean body mass/day for 7 days (approximately 20 g/day) followed by 4 weeks at 0.075 g/kg lean body mass/day for 28 days (approximately 5 g/day) experienced no significant change in ICW, ECW, or TBW [40]. Furthermore, resistance-trained males who consumed creatine supplementation (20 g/day for seven days followed by 5 g/day for 21 days) had no significant increase in ICW, ECW, or TBW [41]. Similarly, males and females ingesting creatine (0.03 g/kg/day for six weeks) experienced no significant increase in TBW [42]. Six weeks of creatine supplementation in non-resistance-trained males at a dosage of 0.3 g/kg lean body mass for five days followed by 0.075 g/kg lean body mass for 42 days produced no significant changes in TBW [43]. In contrast, when assessing TBW, ICW, and ECW content before and after 28 days of creatine supplementation in healthy males and females (n = 32), Powers et al. [44] showed that creatine supplementation was effective at increasing muscle creatine content which was associated with an increase in body mass and TBW but did not alter ICW or ECW volumes. In a recent study examining the effects of creatine supplementation combined with resistance exercise for 8 weeks, Ribeiro et al. [45] found a significant increase in TBW (7.0%) and ICW (9.2%) volume compared to placebo (TBW: 1.7%; ICW: 1.6%), with both groups similarly increasing ECW (CR: 1.2% vs. Placebo = 0.6%). Importantly, the ratio of skeletal muscle mass to ICW remained similar in both groups. It is important to highlight that the ICW is an important cellular signal for protein synthesis and thus drives an increase in muscle mass over time [46].
The vast majority of speculation regarding the relationship between creatine supplementation and hair loss/baldness stems from a single study by van der Merwe et al. [61] where college-aged male rugby players who supplemented with creatine (25 g/day for 7 days, followed by 5 g/day thereafter for an additional 14 days) experienced an increase in serum dihydrotestosterone (DHT) concentrations over time. Specifically, DHT increased by 56% after the seven-day loading period, and remained 40% above baseline values after the 14-day maintenance period. These results were statistically significant compared to when the subjects consumed a placebo (50 g of glucose per day for 7 days, followed by 30 g/day for 14 days thereafter). Given that changes in these hormones, particularly DHT, have been linked to some (but not all) occurrences of hair loss/baldness [62], the theory that creatine supplementation leads to hair loss / baldness gained some momentum and this potential link continues to be a common question / myth today. It is important to note that the results of van der Merwe et al. [61] have not been replicated, and that intense resistance exercise itself can cause increases in these androgenic hormones.
The reutilization of stored energy as a strategy for sprint performance has recently been questioned by Haugen et al. [24], as storage and release of elastic energy take time. Human tendons stretch under load, and sprinters should likely minimize the downside of having these elastic connectors. Adding to the argument, world-class performers sprint with considerably higher leg stiffness than their lower performing counterparts [24]. Based on these considerations, sprinters should focus on leg stiffness (e.g., short ground contact time) during plyometric exercises. Interestingly, this approach was utilized with seeming success by coach Carlo Vittori and the Italian School of sprint training already in the 1970s. The best athlete, Pietro Mennea, performed horizontal jumps and skipping exercises with a weight belt, and ground contact time during these exercises never exceeded 100 ms [12]. This contact time is very similar to those obtained by elite sprinters at maximal velocity [24]. Mennea also performed assisted sprints while equipped with a weight belt (weight vests serve the same purpose). Although these training methods offer strong leg stiffness stimulations, they are demanding and probably increase injury risk, particularly for the Achilles tendon. This may explain why most practitioners perform more traditional plyometric drills as bilateral obstacle (hurdle) jumps, multi jump circuits, medicine ball throws, and unilateral bounding exercises [10,11,12,13,14,15,16,17,18]. Although the highest volumes are accomplished during the preparation phase, some plyometric training is performed during the competition season [10, 11, 15, 16].
It is widely believed that an active cool-down is more effective for promoting post-exercise recovery than a passive cool-down involving no activity. However, research on this topic has never been synthesized and it therefore remains largely unknown whether this belief is correct. This review compares the effects of various types of active cool-downs with passive cool-downs on sports performance, injuries, long-term adaptive responses, and psychophysiological markers of post-exercise recovery. An active cool-down is largely ineffective with respect to enhancing same-day and next-day(s) sports performance, but some beneficial effects on next-day(s) performance have been reported. Active cool-downs do not appear to prevent injuries, and preliminary evidence suggests that performing an active cool-down on a regular basis does not attenuate the long-term adaptive response. Active cool-downs accelerate recovery of lactate in blood, but not necessarily in muscle tissue. Performing active cool-downs may partially prevent immune system depression and promote faster recovery of the cardiovascular and respiratory systems. However, it is unknown whether this reduces the likelihood of post-exercise illnesses, syncope, and cardiovascular complications. Most evidence indicates that active cool-downs do not significantly reduce muscle soreness, or improve the recovery of indirect markers of muscle damage, neuromuscular contractile properties, musculotendinous stiffness, range of motion, systemic hormonal concentrations, or measures of psychological recovery. It can also interfere with muscle glycogen resynthesis. In summary, based on the empirical evidence currently available, active cool-downs are largely ineffective for improving most psychophysiological markers of post-exercise recovery, but may nevertheless offer some benefits compared with a passive cool-down. 2ff7e9595c
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