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Introduction: This study characterized a sample of the first women to complete elite United States (US) military training., Methods: Twelve female graduates of the US Army Ranger Course and one of the first Marine Corps Infantry Officers Course graduates participated in 3 d of laboratory testing including serum endocrine profiles, aerobic capacity, standing broad jump, common soldiering tasks, Army Combat Fitness Test, and body composition (dual-energy x-ray absorptiometry, three-dimensional body surface scans, and anthropometry)., Results: The women were 6 months to 4 yr postcourse graduation, 30 ± 6 yr (mean ± SD); height, 1.67 ± 0.07 m; body mass, 69.4 ± 8.2 kg; body mass index, 25.0 ± 2.3 kg·m -2 . Dual-energy x-ray absorptiometry relative fat was 20.0% ± 2.0%; fat-free mass, 53.0 ± 5.9 kg; fat-free mass index, 20.0 ± 1.7 kg·m -2 ; bone mineral content, 2.75 ± 0.28 kg; bone mineral density, 1.24 ± 0.07 g·cm -2 ; aerobic capacity, 48.2 ± 4.8 mL·kg -1 ·min -1 ; total Army Combat Fitness Test score 505 ± 27; standing broad jump 2.0 ± 0.2 m; 123 kg casualty drag 0.70 ± 0.20 m·s -1 , and 4 mile 47 kg ruck march 64 ± 6 min. All women were within normal healthy female range for circulating androgens. Physique from three-dimensional scan demonstrated greater circumferences at eight of the 11 sites compared with the standard military female., Conclusions: These pioneering women possessed high strength and aerobic capacity, low %BF; high fat-free mass, fat-free mass index, and bone mass and density; and they were not virilized based on endocrine measures as compared with other reference groups. This group is larger in body size and leaner than the average Army woman. These elite physical performers seem most comparable to female competitive strength athletes., (Copyright © 2022 Written work prepared by employees of the Federal Government as part of their official duties is, under the U.S. Copyright Act, a "œwork of the United States Government"œ for which copyright protection under Title 17 of the United States Code is not available. As such, copyright does not extend to the contributions of employees of the Federal Government.)

Modern international military deployments in austere environments (i.e., Iraq and Afghanistan) place considerable physiological demands on soldiers. Significant physiological challenges exist: maintenance of physical fitness and body composition, rigors of external load carriage, environmental extremes (heat, cold, and altitude), medical illnesses, musculoskeletal injuries, traumatic brain injuries, post-traumatic stress disorder, and environmental exposure hazards (i.e., burn pits, vehicle exhaust, etc.). To date there is very little published research and no comprehensive reviews on the physiological effects of deployments. The purpose of this paper is to overview what is currently known from the literature related mainly to current military conflicts with regard to the challenges and consequences from deployments. Summary findings include: (1) aerobic capacity declines while muscle strength, power and muscular endurance appear to be maintained, (2) load carriage continues to tax the physical capacities of the Soldier, (3) musculoskeletal injuries comprise the highest proportion of all injury categories, (4) environmental insults occur from both terrestrial extremes and pollutant exposure, and (5) post-deployment concerns linger for traumatic brain injury and post-traumatic stress disorder. A full understanding of these responses will assist in identifying the most effective risk mitigation strategies to ensure deployment readiness and to assist in establishment of military employment standards.

While studies have examined changes in body composition, fitness, and other measures pre- and postdeployment, it is more difficult to characterize physical training practices during deployment. The purpose of this study was to evaluate the association between training frequency during deployment and changes in physical performance, body composition, and perceived health. Eighty-eight Soldiers (men, 76 and women, 12) from the National Guard performed 1 repetition maximum (1RM) bench press, 1RM back squat, and VO2peak testing within 30 days before and 10 days after deployment to Iraq or Afghanistan. Soldiers completed a questionnaire pertaining to aerobic and strength training frequency, as well as perceived changes to health. Soldiers experienced significant (p ≤ 0.05) improvements in upper (11%) and lower body strength (14%), declines in body fat percent (-16%), but no change in VO2peak. About 57% of Soldiers reportedly performed aerobic training ≥3 times per week, whereas 67% performed strength training ≥3 times per week. Soldiers performing aerobic training ≥3 times per week responded differently than those who conducted aerobic training <3 times per week in VO2peak values (2 vs. -8%, p = 0.016). About 42% of Soldiers reported that their health improved, 36% reported no change to their health, and 22% reported that their health had declined. There was a significant association between training frequency and perceived health. About 50-58% of Soldiers who trained ≥3 times per week reported improvements in health during deployment, whereas only 21-24% of Soldiers who trained <3 times per week reported improvements in health for the same period of time. It seems that Soldiers who train ≥3 times per week experience a more advantageous response in terms of fitness levels and perceived health during deployments.

The purpose of this study is to evaluate the effectiveness of aerobic endurance (E), strength (R), and combined endurance and strength (CB) training for improving performance of tactical occupational tasks and determine if combined training interferes with performance enhancements of E or R alone. A total of 56 recreationally active women were randomly placed into four groups: R (n = 18), E (n = 13), CB (n = 15), Control (n = 10). Subjects trained three non-consecutive days per week for 8 weeks. Performance was measured pre-, mid-, and post-training for bench press one-repetition maximum (1-RM), squat 1-RM, bench press throw and squat jump peak power, VO2peak, 3.2 km load carriage (LC), 3.2 km run (run), and repetitive lift and carry (RLC). R and E demonstrated improvements which were generally specific to their training. R improved squat (48.3%) and bench press 1-RM (23.8%), bench press throw (41.9%), RLC (31.3%), and LC (11.5%). E improved run (14.7%), VO2peak (6.2%), squat 1-RM (15.3%), LC (12.9%), and RLC (22.5%). CB improved squat (37.6%) and bench press 1-RM (20.9%), bench press throw (39.6%), VO2peak (7.6%), run (10.4%), LC (13.1%), and RLC (45.5%). Post-training 1-RM squat was greater in R and CB than E, while E completed the 3.2 km load carriage task faster than C. In conclusion, 8 weeks of combined training improved performance in all tactical occupational tasks measured and did not interfere with improvements in strength, power and endurance measures compared to R or E alone.

Insulin-like growth factor-I (IGF-I) is regulated by a number of IGF-binding proteins (IGFBPs) and proteases that influence IGF-I bioactivity. A specific IGF-I kinase receptor activation assay (KIRA) has been developed that determines the ability of IGF-I to activate the IGF-I receptor by quantification of intracellular receptor autophosphorylation on IGF-I binding. KIRA-assessed IGF-I bioactivity has not been utilized within the context of chronic exercise training paradigms. This study measured total and free immunoreactive IGF-I, bioactive IGF-I, and IGFBP-1, -2, and -3 before (Pre), during (Mid), and after (Post) 8 wk of exercise training in young, healthy women, who were randomized into one of four groups: control (n = 10), resistance (n = 18), aerobic (n = 13), and combined (n = 15) exercise training. The training programs were effective in improving physical fitness specific to the exercise mode engaged in: increases were observed for lean mass ( approximately 2%), aerobic fitness (6-7%), and upper (20-24%) and lower (15-48%) body strength (all P values < 0.05). By contrast, no time, group, or interaction effects were observed for the circulating IGF-I system, as immunoreactive total (Pre = 264 +/- 16 microg/l; Mid = 268 +/- 17 microg/l; Post = 271 +/- 17 microg/l), free (Pre = 0.70 +/- 0.1 microg/l; Mid = 0.63 +/- 0.1 microg/l; Post = 0.63 +/- 0.2 microg/l) and bioactive (Pre = 2.35 +/- 0.3 microg/l; Mid = 2.25 +/- 0.3 microg/l; Post = 2.33 +/- 0.3 microg/l) IGF-I were unchanged throughout the study. All IGFBP measures were also unchanged. We conclude that increased lean mass, aerobic fitness, and upper and lower body strength resulting from an 8-wk exercise training programs can occur without concomitant increases in either circulating bioactive or immunoreactive IGF-I, as well as associated IGFBPs. In terms of reflecting positive anabolic neuromuscular outcomes, these data do not support a role for endocrine-derived IGF-I.

Prescribing exercise based on intensity, frequency, and duration of loading may maximize osteogenic responses in bone, but a model of the osteogenic potential of exercise has not been established in humans. In rodents, an osteogenic index (OI) has been used to predict the osteogenic potential of exercise. The current study sought to determine whether aerobic, resistance, or combined aerobic and resistance exercise programs conducted over eight weeks and compared to a control group could produce changes in biochemical markers of bone turnover indicative of bone formation. We further sought to determine whether an OI could be calculated for each of these programs that would reflect observed biochemical changes. We collected serum biomarkers [bone-specific alkaline phosphatase (BAP), osteocalcin, tartrate-resistant acid phosphatase (TRAP), C-terminal telopeptide fragment of type I collagen (CTx), deoxypyridinoline (DPD), 25-hydroxy vitamin D (25(OH)D), and parathyroid hormone (PTH)] in 56 women (20.3+/-1.8 years) before, during and after eight weeks of training. We also measured bone mineral density (BMD) at regional areas of interest using DXA and pQCT. Biomarkers of bone formation (BAP and osteocalcin) increased in the Resistance and Combined groups (p<0.05), while biomarkers of bone resorption (TRAP and DPD) decreased and increased, respectively, after training (p<0.05) in all groups. Small changes in volumetric and areal BMD (p<0.05) were observed in the distal tibia in the Aerobic and Combined groups, respectively. Mean weekly OIs were 16.0+/-1.9, 20.6+/-2.2, and 36.9+/-5.2 for the Resistance, Aerobic, and Combined groups, respectively. The calculated osteogenic potential of our programs did not correlate with the observed changes in biomarkers of bone turnover. The results of the present study demonstrate that participation in an eight week physical training program that incorporates a resistance component by previously inactive young women results in alterations in biomarkers of bone remodeling indicative of increased formation without substantial alterations in markers of resorption.

The aim of this study was to examine the effect of adding a total-body exercise program to an 8-week diet supplemented with glucomannan on weight loss, body composition, blood parameters, and physical performance in overweight men and women. Sedentary men and women who were overweight (body mass index>25 kg m(-2)) (men: 18-57 years, 27.0+/-11.2 years, 177.5+/-7.6 cm, 102.4+/-14.9 kg; women: 18-52 years, 33.4+/-12.1 years, 160.6+/-4.6 cm, 79.9+/-9.3 kg) completed an 8-week diet with 3000 mg glucomannan combined with either no exercise (No-Ex) (10 men, 10 women) or a resistance and endurance exercise training program (Ex) (12 men, 10 women). The diet emphasized healthy food choices and portion size control. The exercise training consisted of 3 weekly sessions of approximately 1 hour of a nonlinear periodized total-body resistance exercise program followed by 30 minutes of endurance exercise. After the intervention, there were reductions (P<.05) in body mass (men, -2.7+/-1.4 and -3.0+/-4.0 kg; women, -2.2+/-1.5 and -3.3+/-1.5 kg; No-Ex and Ex, respectively), fat mass (men, -2.3+/-1.6 and -3.9+/-2.5 kg; women, -2.6+/-1.4 and -3.6+/-1.1 kg; No-Ex and Ex, respectively), total cholesterol (TC) (men, -17.9+/-21.5 and -18.8+/-19.4 mg dL(-1); women, -9.3+/-20.0 and -10.1+/-19.5 mg dL(-1); No-Ex and Ex, respectively), and low-density lipoprotein cholesterol. Exercise significantly improved high-density lipoprotein cholesterol (HDL-C) (No-Ex, -2.0+/-4.7 and -2.3+/-4.5 mg dL(-1) vs Ex, 4.4+/-10.8 and 1.6+/-3.6 mg dL(-1); men and women, respectively), TC/HDL-C ratio, squat and bench press 1-repetition maximum, and distance covered during a shuttle-run test. In addition, exercise appeared to augment the reduction in fat mass (by 63% and 50%; men and women, respectively) and waist circumference, but did not affect total weight loss. Addition of a resistance and endurance exercise training program to a glucomannan diet regimen significantly improved measures of body composition, HDL-C, and TC/HDL-C ratio.

The purpose of this study was to examine changes in body composition (BC) and physical performance tests (PT) resulting from a competitive season in soccer. Twenty-five male collegiate players (age = 19.9 +/- 1.3 years; height = 177.6 +/- 6.4 cm; body mass = 77.6 +/- 8.6 kg, and percentage body fat = 12.8 +/- 5.2%) were tested before (PRE) and after (POST) the 2003-2004 National Collegiate Athletic Association season. The following tests were performed: BC (anthropometric and dual energy x-ray absorptiometry measurements), vertical jump (VJ), 9.1-m (9 m) and 36.5-m (36 m) sprint, lower-body power (LP), total body power (TP), and cardiorespiratory endurance (VO(2)max). Training was divided into soccer-specific training: field warm-up drills, practices, games, and additional conditioning sessions. A daily, unplanned, nonlinear periodization model was used to assign session volume and intensity for strength sessions (total repetitions < or =96 and workload was > or =80% of 1 repetition maximum). For the entire team, body mass significantly increased by 1.5 +/- 0.4 kg from PRE to POST due to a significant increase in total lean tissue (0.9 +/- 0.2 kg). Regionally, lean tissue mass significantly increased in the legs (0.4 +/- 0.0 kg) and trunk (0.3 +/- 0.1 kg). Physical performance variables were very similar for the entire team at PRE and POST; VJ (cm) = 61.9 +/- 7.1 PRE vs. 63.3 +/- 8.0 POST, 9.1-m (s) = 1.7 +/- 0.1 PRE and POST, 36.5-m (s) = 5.0 +/- 0.2 PRE and POST, predicted VO(2)max (ml.kg.min(-1))= 59.8 +/- 3.3 PRE vs. 60.9 +/- 3.4 POST. The only significant improvements across the season were for TP (17.3%) and for LP (10.7%). In conclusion, soccer athletes who begin a season with a high level of fitness can maintain, and in some cases improve, body composition and physical performance from before to after a competitive season. A correct combination of soccer-specific practices and strength and conditioning programs can maintain and develop physical performance, allowing a soccer athlete to perform optimally throughout pre-, in-, and postseason play.

The purpose of this study was to determine the impact of a very slow (VS) velocity and a self-selected volitional (VOL) velocity at varying intensities on repetition number, peak force, peak power, and total volume in the squat and shoulder press exercises. On separate testing days, 9 resistance trained men (age: 23.9 +/- 2.5 years; height: 174.8 +/- 6.5 cm; body mass: 80.1 +/- 12.4 kg) performed a squat (SQ) and shoulder press (SP) exercise at 60 or 80% of 1 repetition maximum (1RM) at either VOL or VS (10-second eccentric and 10-second concentric actions) velocity for as many repetitions as possible. Force, power, and volume (repetitions x kg) were also determined. Subjects performed significantly fewer repetitions (p < or = 0.05) in the VS exercises (60% VS SQ 5 +/- 1 vs. VOL SQ 24 +/- 2; 80% VS SQ 2 +/- 0 vs. VOL SQ 12 +/- 1; 60% VS SP 4 +/- 1 vs. VOL SP 14 +/- 2; 80% VS SP 1 +/- 0 vs. VOL SP 6 +/- 1). Peak force and power were significantly higher at the VOL speed (peak force [in newtons]: 60% VS SQ 564.4 +/- 77.3 vs. VOL SQ 1229.0 +/- 134.9 N; 80% VS SQ 457.3 +/- 27.9 vs. VOL SQ 1059.3 +/- 104.7 N; 60% VS SP 321.6 +/- 37.8 vs. VOL SP 940.7 +/- 144.8 N; 80% VS SP 296.5 +/- 24.7 vs. VOL SP 702.5 +/- 57.7 N; and peak power [in watts]: 60% VS SQ 271.2 +/- 40.1 vs. VOL SQ 783.2 +/- 129.1 W; 80% VS SQ 229.3 +/- 49.5 vs. VOL SQ 520.2 +/- 85.8 W; 60% VS SP 91.3 +/- 21.9 vs. VOL SP 706.6 +/- 151.4 W; 80% VS SP 78.1 +/- 19.8 vs. VOL SP 277.6 +/- 46.4 W). VOL speed elicited higher total volume than the VS velocity. The results of this study indicate that a VS velocity may not elicit appropriate levels of force, power, or volume to optimize strength and athletic performance.

Introduction: The U.S. Army Occupational Physical Assessment Test (OPAT) is a pre-enlistment physical employment screening assessment developed to place recruits and soldiers into Military Occupational Specialties (MOSs) based on their physical capabilities in order to optimize performance and limit injury. The OPAT consists of the seated power throw (SPT), strength deadlift (SDL), standing long jump, and interval aerobic run. During the scientific validation of the OPAT, two variants of the SPT and two variants of the SDL were used. Although the OPAT was validated using both variants for each test, U.S. Army scientists and policymakers have received queries regarding how these variants compare to each other. Therefore, the purpose of this study was to compare different variants of the SPT and SDL.Materials and Methods: Thirty-two participants (14 male and 18 female) between the ages of 18 and 42 years visited the laboratory on one occasion and performed two variants of the SPT (seated on the ground [the current OPAT standard] versus seated in a chair with a 35 cm seat height) and two variants of the SDL (using a hex-bar [the current OPAT standard] versus using paired dumbbells). Testing order for the different variants was randomized. The protocol was approved by the U.S. Army Medical Research and Development Command Institutional Review Board.Results: Performing the SPT from a chair significantly (P < .05) increased performance when compared to performing the SPT from the ground (5.4 ± 1.3 m versus 5.0 ± 1.4 m, respectively). Values for the two SPT variants were correlated (tau = 0.90). Performing the SDL using the hex-bar significantly increased the maximal weight lifted when compared to performing the SDL using paired dumbbells (86.9 ± 18.4 kg versus 83.1 ± 18.0 kg, respectively). Values for the two SDL variants were correlated (tau = 0.83).Conclusions: Performing different variants of the SPT and SDL influenced the resulting score. Although these findings do not alter the administration or scoring of the OPAT, they do provide a valuable reference in the event of future inquiries regarding the development of the OPAT. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the reliability and construct validity of a battery of tests designed to assess soldier task performance. In the first part of the study (designed to assess test-retest reliability), 33 enlisted soldiers (31 men, 2 women; 23 ± 3 years; 1.75 ± 0.08 m; and 81.4 ± 12.8 kg) completed a 4-event “soldier task test battery” (STTB) on 4 occasions, each separated by at least 1 week. The STTB consisted of the following tests, in order: (a) 30-m grenade throw for accuracy; (b) running long jump while wearing a 20.5-kg load; (c) 1 repetition maximum box lift; and (d) 3.2-km load carriage time trial while wearing a 33-kg load. In the second part of the study (designed to assess construct validity), 41 male soldiers (22 ± 3 years; 1.75 ± 0.08 m; and 81.4 ± 12.9 kg) completed the STTB and a series of physical fitness tests. The physical fitness tests included measurements of body composition, muscular strength, muscular power, muscular endurance, and cardiovascular endurance. Overall performance on the STTB (reflected by the sum of z-scores across individual tests) demonstrated an intraclass correlation coefficient of 0.95 and was correlated to lean mass, Vo2 peak, and measures of muscular strength and power. Lean body mass and standing long jump predicted performance on the STTB (R2 = 0.41). In conclusion, this STTB can reliably assess performance of soldiering tasks. The relationships between the STTB and physical fitness tests can be used to develop training programs to prepare soldiers to perform physically demanding tasks. [ABSTRACT FROM AUTHOR]

Nearly every physically active person encounters periods in which the time available for exercise is limited (e.g., personal, family, or business conflicts). During such periods, the goal of physical training may be to simply maintain (rather than improve) physical performance. Similarly, certain special populations may desire to maintain performance for prolonged periods, namely athletes (during the competitive season and offseason) and military personnel (during deployment). The primary purpose of this brief, narrative review is to identify the minimal dose of exercise (i.e., frequency, volume, and intensity) needed to maintain physical performance over time. In general populations, endurance performance can be maintained for up to 15 weeks when training frequency is reduced to as little as 2 sessions per week or when exercise volume is reduced by 33-66% (as low as 13-26 minutes per session), as long as exercise intensity (exercising heart rate) is maintained. Strength and muscle size (at least in younger populations) can be maintained for up to 32 weeks with as little as 1 session of strength training per week and 1 set per exercise, as long as exercise intensity (relative load) is maintained; whereas, in older populations, maintaining muscle size may require up to 2 sessions per week and 2-3 sets per exercise, while maintaining exercise intensity. Insufficient data exists to make specific recommendations for athletes or military personnel. Our primary conclusion is that exercise intensity seems to be the key variable for maintaining physical performance over time, despite relatively large reductions in exercise frequency and volume. [ABSTRACT FROM AUTHOR]

Muscle power and strength decrease with age leading to reduced independence and increased health risk from falls. Creatine supplementation can increase muscle power and strength. The purpose of this study was to examine the effects of 7 days of creatine supplementation on body composition, muscular strength, and lower-body motor functional performance in older women. Thirty 58–71 year old women performed three test sessions (T1–T3) each separated by one week. Each session consisted of one repetition maximum tests for bench press and leg press, and isometric hand-grip, tandem gait, upper-body ergometer, and lower-body ergometer tests. Following T2, subjects were assigned to a creatine monohydrate (0.3 g kg body mass−1 for 7 days) (CR: 63.31 ± 1.22 year, 160.00 ± 1.58 cm, 67.11 ± 4.38 kg) or a placebo (PL: 62.98 ± 1.11 year, 162.25 ± 2.09 cm, 67.84 ± 3.90 kg) supplementation group. CR significantly ( P < 0.05) increased bench press (1.7 ± 0.4 kg), leg press (5.2 ± 1.8 kg), body mass (0.49 ± 0.04 kg) and fat free mass (0.52 ± 0.05) and decreased completion time on the functional tandem gait tests from T2–T3. No significant changes were found for PL on any of the measured variables. No adverse side-effects were reported by either group. Short-term creatine supplementation resulted in an increase in strength, power, and lower-body motor functional performance in older women without any adverse side effects [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this investigation was to examine the effects of amino acid supplementation on muscular performance and resting hormone concentrations during resistance training overreaching. Seventeen resistance-trained men were randomly assigned to either an amino acid (AA) or a placebo (P) group and underwent 4 weeks of total-body resistance training designed to induce a state of overreaching. The protocol consisted of two 2-week phases (phase 1, 3 sets of 8 exercises performed for 8-12 repetitions; phase 2, 5 sets of 5 exercises performed for 3-5 repetitions). Muscle strength and resting blood samples were determined before (T1) and at the end of each training week (T2-T5). One-repetition maximum squat and bench press decreased at T2 in the P group but not in the AA group; both groups showed similar increases in strength at T3 to T5. Significant elevations in serum creatine kinase and uric acid were observed at T2 in the P group; the elevation in creatine kinase correlated highly to reductions in 1-repetition maximum squat (r = −0.67, r 2 = 0.45). Significant elevations in serum sex hormone–binding globulin were observed during overreaching in the P group from T2 to T5; this response was abolished in the AA group. Significant reductions in total testosterone were observed in the P group at T4 compared with T1, and total testosterone values were higher for the AA group than for the P group from T2 to T4. Serum 22-kd growth hormone concentrations were elevated at T2 to T5 in P group only. No differences were observed in resting cortisol and insulinlike growth factor 1. Hemoglobin concentrations were significantly reduced at T2 to T5 in the P group. These results indicate that the initial impact of high-volume resistance training is muscle strength reduction and hormonal/biochemical alterations. It appears that amino acid supplementation is effective for attenuating muscle strength loss during initial high-volume stress, possibly by reducing muscle damage by maintaining an anabolic environment. [Copyright &y& Elsevier]

Airborne ultrafine and fine particulate matter (PM 1 from fossil-fueled internal combustion engines may cause abnormal airway narrowing. Because of high PM 1 exposure from ice resurfacing machines, the ice-rink athlete is especially vulnerable to PM 1 toxicity. The purpose of this study was to evaluate protection by a single dose of montelukast in college ice hockey players following PM 1 exposure exercise. Nine male ice hockey players (age 19.3 &PlusMinus; 1.22 yr) performed 4 randomized, double-blinded, high-intensity, 6-min cycle ergometer trials in low [PM 1 ] (2260 &PlusMinus; 500 particles/cm 3 ) and high [PM 1 ] (348,600 &PlusMinus; 121,600 particles/cm 3 ) after placebo or montelukast. Pre- and postspirometry showed similar peak FEV 1 (forced expiratory volume in 1 s) falls between placebo and montelukast after low [PM 1 ] trials (14.5 &PlusMinus; 18.06 vs. 9.5 &PlusMinus; 11.75% of baseline, respectively). Peak FEV 1 falls after high [PM 1 ] trials were greater for placebo than for montelukast (17.3 &PlusMinus; 9.79% vs. 1.7 &PlusMinus; 5.77% of baseline; p < .0001). High [PM 1 ] FEV 1 fall after exercise following montelukast ingestion was less than after exercise following placebo ingestion under high and low [PM 1 ] conditions and after exercise following montelukast ingestion under low [PM 1 ] conditions at 5, 10, and 15 min postchallenge (p < .004, .0006, .009, respectively). Montelukast provided greater protection against bronchoconstriction after exercise during high [PM 1 ] than low [PM 1 ] exposure (&nvsim;90% vs. &nvsim;35%), suggesting that bronchoconstriction from PM 1 exposure is predominately leukotriene mediated. The precise mechanism of airborne PM 1 -induced leukotriene-mediated airway narrowing remains unclear. [ABSTRACT FROM AUTHOR]

Strenuous physical exercise can induce damage and injury to muscle tissue that is manifested as soreness, a decreased range of motion, swelling, pain, and impaired functional capacity. Compression is a therapeutic technique widely used in the treatment of muscle and other soft tissue injuries, though evidence in support of this remedial therapy has until recently being largely anecdotal. Recent scientific research has indicated that external compression can be an effective treatment that minimises swelling, improves the alignment and mobility of scar tissue, and improves proprioception in an injured joint consequent to eccentric damage models and DOMS. The principles behind compressive treatment methods are based on known principles affecting the lymphatic system, reducing oedema, skeletal muscle contractions, local pressure gradients, and the influence of gravity. The rationale for applying compression to injured tissue are, (i) its theoretical ability to reduce oedema via the creation of an external pressure gradient, (ii) by reducing the space available for swelling to accumulate, haemorrhage and haematoma formation can be decreased, and (iii) providing mechanical support that can facilitate the capacity to produce force which is critical for rehabilitation. Compression involves a "dynamic immobilisation" strategy that allows for greater neural input and the capacity for limited movement during the recovery process. This treatment protocol represents an easily administered therapy that can be used effectively without great financial cost. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the effects of chromium supplementation on glycogen synthesis after high-intensity exercise. The aim of the study is to assess the potential of chromium picolinate supplementation in humans to enhance the rate of glycogen synthesis after intense exercise. Here, sixteen overweight men aged 20-23 were recruited from the student population and were supplemented with chromium as picolinate. Results show that chromium supplementation did not augment glycogen synthesis during recovery from high-intensity exercise and high-carbohydrate feeding, although there was a trend for lower phosphatidylinositol 3-kinase activity.