THE EFFECTS OF A DYNAMIC WARM-UP USING A RESPIRATORY TRAINING MASK ON VERTICAL JUMP PERFORMANCE

Emilee M. Bounds, John H. Sellers, Jessica A. Schnaiter, Bert H. Jacobson FACSM; Oklahoma State University, Stillwater, Oklahoma Respiratory training masks have been utilized to increase warm-up intensity via increased respiration rate, heart rate, and body temperature without inducing muscular fatigue. However, the majority of such claims appear to be based on anecdotal evidence as opposed to evidence-based research. PURPOSE: The purpose of this study was to investigate the effect of a high-intensity warm-up (HWU) using a respiratory training mask on vertical jump (VJ) performance in Division I American football athletes. METHODS: Seventeen male (mean ± SD: age = 17.94 ± .75 years, mass = 104.43 ± 23.02 kg, height 184.93 ± 7.06 cm) American football athletes from the NCAA Division I level were recruited to participate in this study from a Midwestern university. Participants were informed of risks, and after completing an informed consent form, completed two testing sessions to assess VJ performance. Prior to each testing session, a member of the university’s strength and conditioning staff led the participants through a dynamic warm-up that focused on lower body musculature. For one testing session, participants completed the warm-up (WU) without the respiratory training mask, while for the other testing session, participants completed the warm-up with the respiratory training mask. The respiratory training mask was set so as to increase the athlete’s respiratory efforts 12-fold in order to create the high-intensity warm-up (HWU). After completing the warm up, participants executed three counter-movement vertical jumps (VJ). For data analysis purposes, values from each participant’s highest VJ performance were selected from both the control (WU) and experimental (HWU) sessions. A one-way repeated measure analysis of variance (ANOVA) design was used to assess differences between control and HWU results. All statistical analyses were performed using SPSS (Version 21.0 for Windows; SPSS, Chicago, Illinois) with statistical significance set a p \u3c .05. RESULTS: No statistical difference was found (p = 0.07) between vertical jump performance using a standard warm-up and high-intensity warm up. CONCLUSION: Using a respiratory resistance mask for a warm-up does not impact vertical jump height, and practitioners should exercise caution when prescribing its use to increase performance

EFFECTS OF A DYNAMIC WARM-UP USING A RESISTANCE TRAINING MASK ON SPRINT PERFORMANCE

Jessica A. Schnaiter, John H. Sellers, Emilee M. Bounds, Bert H. Jacobson *FACSM Oklahoma State University, Stillwater, OK In recent years, coaches and athletes alike have taken a keen interest in maximizing the efficiency of a dynamic warm-up without inducing muscular fatigue. One proposed method of doing so is using a respiratory training mask to provide breathing resistance to increase the intensity of a warm-up. Though there is limited empirical evidence on the topic, many athletes have adopted this warm-up strategy, possibly due to testimonials from high-profile athletes in their respective sports. PURPOSE: The purpose of this study was to investigate the effect of a high-intensity warm-up (HWU) using a respiratory training mask on sprint performance, heart rate measures (HR), and ratings of perceived exertion (RPE) in Division I football athletes using a timing system. METHODS: Seventeen male (mean ± SD: age = 17.94 ± .75 years, weight = 104.43 ± 23.02 kg, height 184.93 ± 7.06 cm) American football athletes from a NCAA Division I level were recruited to participate in this study from a Midwestern university. Athletes were informed of risks, and upon completing an informed consent document, completed 2 testing sessions separated by 7 days. Each testing session took place on artificial turf in the university’s indoor training facility at the same time of day. Both testing sessions began with a warm-up (WU) under the instruction of a member of the university’s strength and condition staff. The WU consisted of dynamic exercises targeting the lower body musculature. During the initial visit, participants completed the dynamic WU and testing without a respiratory training mask. During the second visit, the HWU was completed with the respiratory training mask set to increase the resistance level of breathing by 12-fold. Upon completion of the HWU, participants removed the mask and performed 5 × 10-meter sprints. A one-way repeated measures analysis of variance (ANOVA) design was used to assess differences between control and experimental results. All statistical analyses were performed using SPSS (Version 21.0 for Windows; SPSS, Chicago, Illinois) with statistical significance set a p \u3c .05. RESULTS: Sprint time was not significantly different after a HAWU using a respiratory training mask (p = 0.874). CONCLUSION: These findings do not suggest the use of a respiratory resistance training mask during a dynamic warm-up is useful in increasing 10-meter sprint times for football players. Athlete’s performance on repeated sprints was not improved after using a resistance mask; however, performance was also not hindered

Data-driven design of metal–organic frameworks for wet flue gas CO<inf>2</inf> capture

Limiting the increase of CO2 in the atmosphere is one of the largest challenges of our generation1. Because carbon capture and storage is one of the few viable technologies that can mitigate current CO2 emissions2, much effort is focused on developing solid adsorbents that can efficiently capture CO2 from flue gases emitted from anthropogenic sources3. One class of materials that has attracted considerable interest in this context is metal–organic frameworks (MOFs), in which the careful combination of organic ligands with metal-ion nodes can, in principle, give rise to innumerable structurally and chemically distinct nanoporous MOFs. However, many MOFs that are optimized for the separation of CO2 from nitrogen4–7 do not perform well when using realistic flue gas that contains water, because water competes with CO2 for the same adsorption sites and thereby causes the materials to lose their selectivity. Although flue gases can be dried, this renders the capture process prohibitively expensive8,9. Here we show that data mining of a computational screening library of over 300,000 MOFs can identify different classes of strong CO2-binding sites—which we term ‘adsorbaphores’—that endow MOFs with CO2/N2 selectivity that persists in wet flue gases. We subsequently synthesized two water-stable MOFs containing the most hydrophobic adsorbaphore, and found that their carbon-capture performance is not affected by water and outperforms that of some commercial materials. Testing the performance of these MOFs in an industrial setting and consideration of the full capture process—including the targeted CO2 sink, such as geological storage or serving as a carbon source for the chemical industry—will be necessary to identify the optimal separation material

Interrelationships among lean bundles and their effects on operational performance

The aim of our research is to disentangle the complex relations among lean bundles and operational performance. In particular, we focus on the direct and mediating effects on operational performance of three of the main lean manufacturing bundles, namely Just in Time (JIT), Total Quality Management (TQM) and Human Resource Management (HRM). We run statistical analysis on the High Performance Manufacturing round III database, a survey involving 266 plants in nine countries across three different industries. Our results show that JIT and TQM have a direct and positive effect on operational performance while HRM has a mediated effect on it. Theoretical and managerial implications of our findings are then drawn and discussed

Data-driven design of metal-organic frameworks for wet flue gas CO2 capture.

Limiting the increase of CO2 in the atmosphere is one of the largest challenges of our generation1. Because carbon capture and storage is one of the few viable technologies that can mitigate current CO2 emissions2, much effort is focused on developing solid adsorbents that can efficiently capture CO2 from flue gases emitted from anthropogenic sources3. One class of materials that has attracted considerable interest in this context is metal-organic frameworks (MOFs), in which the careful combination of organic ligands with metal-ion nodes can, in principle, give rise to innumerable structurally and chemically distinct nanoporous MOFs. However, many MOFs that are optimized for the separation of CO2 from nitrogen4-7 do not perform well when using realistic flue gas that contains water, because water competes with CO2 for the same adsorption sites and thereby causes the materials to lose their selectivity. Although flue gases can be dried, this renders the capture process prohibitively expensive8,9. Here we show that data mining of a computational screening library of over 300,000 MOFs can identify different classes of strong CO2-binding sites-which we term 'adsorbaphores'-that endow MOFs with CO2/N2 selectivity that persists in wet flue gases. We subsequently synthesized two water-stable MOFs containing the most hydrophobic adsorbaphore, and found that their carbon-capture performance is not affected by water and outperforms that of some commercial materials. Testing the performance of these MOFs in an industrial setting and consideration of the full capture process-including the targeted CO2 sink, such as geological storage or serving as a carbon source for the chemical industry-will be necessary to identify the optimal separation material