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Introduction This study investigated the effects of a beet nitric oxide enhancing (NOE) supplement comprised of nitrite and nitrate on cycling performance indices in trained cyclists. Methods: Subjects completed a lactate threshold test and a high-intensity interval (HIIT) protocol at 50% above functional threshold power with or without oral NOE supplement. Results: NOE supplementation enhanced lactate threshold by 7.2% (Placebo = 191.6 ± 37.3 W, NOE = 205.3 ± 39.9; p = 0.01; Effect Size (ES) = 0.40). During the HIIT protocol, NOE supplementation improved time to exhaustion 18% (Placebo = 1251 ± 562s, NOE = 1474 ± 504s; p = 0.02; ES = 0.42) and total energy expended 22.3% (Placebo = 251 ± 48.6 kJ, NOE = 306.6 ± 55.2 kJ; p = 0.01; ES = 1.079). NOE supplementation increased the intervals completed (Placebo = 7.00 ± 2.5, NOE = 8.14 ± 2.4; p = 0.03; ES = 0.42) and distance cycled (Placebo = 10.9 ± 4.0 km, NOE = 13.5 ± 3.9 km; p = 0.01; ES = 0.65). Also, target power was achieved at a higher cadence during the HIIT work and rest periods (p = 0.02), which enhanced muscle oxygen saturation (SmO2) recovery. Time-to-fatigue was negatively correlated with the degree of SmO2, desaturation during the HIIT work interval segment (r = −0.67; p 0.008), while both SmO2 desaturation and the SmO2 starting work segment saturation level correlated with a cyclist's kJ expended (SmO2 desaturation: r = −0.51, p = 0.06; SmO2 starting saturation: r = 0.59, p = 0.03). Conclusion: NOE supplementation containing beet nitrite and nitrate enhanced submaximal (lactate threshold) and HIIT maximal effort work. The NOE supplementation resulted in a cyclist riding at higher cadence rates with lower absolute torque values at the same power during both the work and rest periods, which in-turn delayed over-all fatigue and improved total work output., Graphical abstract Image 1, Highlights • Beet nitric oxide enhancing supplementation comprised of inorganic nitrite and nitrate, but relying predominately on nitrite for nitric oxide production, improved lactate threshold power by 7.2% compared to placebo in trained cyclists and triathletes. • Beet nitric oxide enhancing supplementation increased the total number of work intervals completed while improving time to exhaustion 18%, the total energy expenditure expended during high intensity intervals 22.3%, and the total cycling distance completed 23.9% compared to placebo. • Beet nitric oxide enhancing supplementation improved performance by allowing each subject to maintain interval power targets at higher cadences and lower absolute torque which in turn enhanced SmO2 recovery during the rest intervals. • A beet nitric oxide enhancing supplement with an appropriate concentration of inorganic nitrite can be an effective ergogenic aid, and response faster than a nitrate supplement.

The present investigation examined the ability of two threshold detection analyses (maximum distance, Dmax; modified maximum distance, mDmax) in identifying the near-infrared spectroscopy (NIRS) threshold, a lactate threshold (LT) estimate, from exercising tissue oxygen saturation (StO(2)) responses. Additionally, the test-retest reliability of exercising StO(2) and total hemoglobin concentration (THC) responses were examined at moderate and peak cycling intensities. Fourteen healthy, recreationally active participants performed maximal incremental step cycling tests (+25 W / 3 minutes) to volitional fatigue on two separate occasions while StO(2) and THC of the vastus lateralis were monitored. Exercising blood [lactate] was collected during Session One. LT and NIRS thresholds (NIRS1, NIRS2) were then determined using Dmax and mDmax threshold analyses. Significant (p < 0.05), moderate correlations were detected between LT and NIRS1 when using Dmax (LT = 130 ± 49 W, NIRS1 = 136 ± 34 W, r = 0.690), but not for mDmax (r = 0.487). No significant test-retest reliability for the NIRS thresholds were observed for Dmax (ICC = 0.351) or mDmax (ICC = 0.385). Exercising StO(2) responses demonstrated good reliability (ICC = 0.841–0.873) while exercising THC responses demonstrated moderate-good reliability (ICC = 0.720–0.873) at moderate and peak exercise intensities. The results of this study suggest that neither the Dmax nor mDmax threshold analyses should be used to estimate the LT due to the unreliable detection of the NIRS threshold from session to session.

Neuromuscular fatigue is a common complaint in Crohn’s disease (CD) patients. A correlation between serum vitamin D concentrations and neuromuscular function has been found in the elderly or non-ambulant populations. The aim of this study was to determine whether CD patients exhibit impaired neuromuscular function and if so, is there a link between vitamin D and neuromuscular function. Crohn’s disease patients (n = 19) with at least one prior small bowel resection and matched controls (n = 19) underwent muscle strength and endurance testing, vitamin D, and nerve function analysis. Knee extension and flexion peak torque (Nm/kg) were greater in the control group than in the CD patients (P = 0.04 and 0.014, respectively. A significant difference was found between fatigue rates of the rectus femoris (P = 0.015) between CD patients and controls, but no difference was found in serum vitamin D levels between groups (P = 0.317). Knee extension and flexion torque measurements, with age as a covariate, were compared with high and low vitamin D levels. Those subjects with high serum vitamin D levels had a significantly greater extension peak torque (P = 0.045) and extension average torque (Nm/kg) (P = 0.014) than those with low levels. Crohn’s disease patients with sufficient vitamin D levels experienced a 43 % greater extension peak torque. Although vitamin D deficiency has been associated with neuromuscular dysfunction, there were no differences in serum vitamin D levels between the CD and healthy controls to explain the decreased muscle strength.

Androstenedione, 4-androstenediol, 5-androstenediol, 19-norandrostenediol and 19-norandrostenedione are commonly referred to as "Andro" prohormones. Over the last few years, supplementation using these prohormones has been aggressively marketed to the general public. Supplement manufacturers often claim that Andro use improves serum testosterone concentrations, increases muscular strength and muscle mass, helps to reduce body fatness, enhances mood, and improves sexual performance. However, to date, most studies contradict these claims. In contrast, several studies using oral Andro related prohormones show that Andro use can abnormally elevate estrogen related hormones as well as alterations in hormonal markers (i.e., abnormal elevations in serum estrogen) thought to increase a person's risk for developing prostate or pancreatic cancers. In addition, most studies also indicate that significant declines in high-density lipoproteins occur leading to an increased cardiovascular disease risk. Thus, to date, the current research base suggests that Andro prohormone use does not support manufacturer claims. But it does suggest there should be strong concerns regarding long-term oral Andro prohormone use, especially regarding its effects on blood lipids and estrogen hormone profiles. Key words: resistance exercise, androstenedione, androstenediol, anti-aging

51 kindergarten children participated to assess how various fitness components, ½-mile run, the Prudential PACER test, body composition, shoulder stretch, trunk lift, sit-and-reach, curl-up, and flex arm-hang related to motor performance on the Bruininks-Oseretsky test battery including running, speed, agility, balance, bilateral coordination, and strength. All values recorded in the fitness components were compared with standardized motor skill scores. Analysis indicated that ½-mile run performance was significantly correlated with body weight and relative body fat, showing that as body weight or relative body fat increased run performance times were slower. Comparisons between the fitness parameters and motor skills indicated that the ½-mile run performance also was negatively correlated with measures of balance, bilateral coordination, and strength while the Prudential PACER test was positively correlated with strength. During continuous walk-jog movements (half-mile run) in a relatively homogeneous sample, increases in body size improved balance, bilateral coordination, and strength but negatively affected running during the ½-mile fitness test. In more interval-related activities such as the Prudential PACER test, an increase in strength was related to improved performance.

The purpose of this study was to determine how differences in hydration states and ion content of hydrating fluids affected bioelectrical impedance (BI) and hydrostatic weighing (HW) measurements.Fifteen athletic subjects aged 19-56 yr were recruited. Relative body fat (%), fat-weight (FW), and fat-free weight (FFW) were assessed using BI and HW under normal conditions (N), hypohydration (HPO), rehydration (RHY), and superhydration (SHY) states. During the RHY and SHY trial periods, subjects were hydrated with either distilled water or an electrolyte solution (ELS). HPO and SHY levels were set at 3% of each person's normally hydrated body weight.Comparison between the distilled water and the ELS trials indicated that hydration solution had no effect on BI or HW. Thus, the results presented are the trial means of both hydration solutions combined. Both BI and HW were shown to be highly test-retest reliable (r-values: 0.96 and 0.99, respectively). The effects of exercise induced HPO followed by RHY on body composition values indicated that HW was very stable across measurement periods while BI was not. From N to the HPO state, BI %BF declined from 14.4 +/- 5.3% to 12.3 +/- 5.3%, respectively. After RHY, BIA %BF increased to 15.5 +/- 5.8%. Similar findings occurred when subjects were superhydrated (N-BI = 13.2 +/- 5.3%; SHY-BI = 15.4 +/- 5.6%). With a comparison of the intercepts and slopes of HW and BIA for the N and SHY states, it was clear hydration status significantly affected the intercepts (HW: 0.37 vs. BI: 1.85) and not the slopes (HW: 1.00 vs BI: 0.99). As a result, a majority of all fluid changes were interpreted as FW by BI. During HPO, 82% of the weight loss was considered FW while during RHY or SHY, 128% and 85% of the water weight regain/gain was considered FW.These results indicate that BI is not a valid technique in athletes, especially when wanting to determine body composition effects of training/detraining. This study indicates that even small fluid changes such as those that occur with endurance training may be interpreted incorrectly as changes in an athlete's body fat content.

This study's purpose was to determine the validity of near-infrared interactance (NIR) and bioelectric impedance (BIA) in tracking changes in body composition over 12 wk of either a high intensity endurance (ET) or resistance (RT) training program in nondieting weight-stable untrained males. Prior to and following the control or training period, each subject completed a series of body composition analyses including hydrostatic weighing (HW) with a measurement of residual volume: anthropometric measurements including height, weight, skinfold, and girth: BIA measurement: and NIR measurements. Based on the HW results, there were no significant body composition changes in the control group. For the ET group, a significant decline in relative body fat resulted from a reduction in fat weight (FW) with no change in fat-free weight (FFW). In the RT group, both a significant decline in FW and an increase in FFW contributed to this group's decline in relative body fat. Tracking changes in relative body fat, FW, and FFW, skinfolds agree reasonably well with HW in all groups while BIA and NIR did not always track body composition changes well. For example, SF and BIA were significantly correlated with the changes in FFW (HW = +4.1%, SF = +4.5%. BIA = +3.1%. NIR = -0.7%) observed in the RT group compared to HW (SF: r-value = 0.45, SEE = 2.5; BIA: r = 0.33, SEE = 3.4) while the NIR measurements were nonsignificant (r = 0.09, SEE = 5.0). Interestingly, NIR underestimated the gain in FFW in the resistance trained group while BIA underestimated the changes in relative body fat. FW, and FFW in the endurance trained group. Based on these results, BIA and NIR appear not to be appropriate measurement tools for tracking body composition changes in endurance and resistance training individuals respectively.

This study determined the reliability of measuring resting metabolic rate (RMR) with COSMED's FitMate™ metabolic system using a canopy dilution set-up compared with a previously validated COSMED QUARK CPET research-based system in 30 healthy adults (age: 28.4 ± 7.0 yrs, weight: 79.9 ± 20.2 kg, percent body fat: 22.5 ± 8.6%). The FitMate was developed as an inexpensive metabolic system for RMR and fitness testing. Subjects were randomly assigned to start testing on either the FitMate or Quark CPET for four 10-minute measurements. Test-retest intraclass correlations were 0.95-0.99, p ≤ 0.0001 for all parameters tested. Ve, RMR, VO2, and heart rate were not significantly different between the two systems. These results suggest that the FitMate is a reliable canopy dilution system for RMR measurements in healthy adults.

The effects of a nonselective β-adrenergic blocking agent with (pindolol) and without (propranolol) intrinsic sympathomimetic activity properties, compared with placebo-controlled conditions, on metabolic and cardiorespiratory function during long-duration (2 hours) physical activity were examined. After initial cardiorespiratory testing, subjects performed 2-hour walks at 25 and 45% of maximal oxygen consumption (VO2max) under each of the following 3 treatments: pindolol, propranolol and placebo. Medication distribution was randomized and double-blinded. A supine resting blood pressure and electrocardiogram were obtained before each exercise trial. Oxygen consumption, heart rate, stroke volume, cardiac output and blood pressure were determined after 5 minutes of quiet sitting and every 30 minutes during each 2-hour exercise trial. Cardiac output was not significantly different at rest or during exercise, comparing pindolol and propranolol with placebo conditions. Cardiac output tended to decrease over time earlier during propranolol treatment for the 25% VO2max trials in trained normotensive subjects than for the other treatments. Cardiac output decreased at approximately the same time across treatments during the 45% VO2max trials in trained normotensive and untrained hypertensive groups. Finally, owing to the observation that a reduction in cardiac output was delayed or prevented in trained normotensive subjects when compared with that in untrained hypertensives while exercising at 25% VO2max, developing a subject's cardiovascular fitness level may be important in the maintenance of cardiac output during extended periods of low-tomoderate physical activities while under the influence of β-adrenergic blockade.

The effects of either 12-wk of high-intensity endurance or resistance training on resting metabolic rate (RMR) were investigated in 47 males aged 18-35 y. Subjects were randomly assigned to either a control (C), resistance-trained (RT) or endurance-trained (ET) group. After training both exercise groups showed significant declines in relative body fat either by reducing their total fat weight and maintaining fat-free weight (ET) or by reducing their total fat weight and increasing fat-free weight (RT). RMR did not significantly change after either training regimen although a small decline in energy intake was observed along with an increase in energy expenditure [ET, 2.721 MJ (650 kcal) per training day]. These results suggest that both endurance and resistance training may help to prevent an attenuation in RMR normally observed during extended periods of negative energy balance (energy intake less than expenditure) by either preserving or increasing a person's fat-free weight.

A cross-sectional study was designed to deter- mine the relationship between aerobic fitness and resting met- abolic rate (RMR) in 69 males exhibiting a wide range of aerobic fitness levels (VO2max = 32.8-78. 1 mL . kg� . min�). The re- sults ofthis study indicated that RMR was not significantly dif- ferent between trained and untrained individuals when expressed in Id . kg fat-free weight� . hror using an ANCOVA with fat- free weight as the covariate and RMR as the dependent variable (F ratio = 0.353, P < 0.70). In addition, this study also failed to support a previously suggested hypothesis that an elevated RMRmay only be observed in those individuals exhibiting both high VO2max values and currently training a minimum of 12- 16 h/wk. Thus, the results of this study strongly suggest that RMR is independent of both a person's current aerobic level and training status. Am J C/in Nutr 1992;55:795-801.

The effect of beta-adrenergic blockade on stroke volume (SV) at increasing submaximal exercise intensities was studied in 12 endurance-trained normotensive and 12 untrained hypertensive (diastolic blood pressure greater than 95 mm Hg) men, aged 18 to 34 years. Subjects were assigned to each of 3 treatments in a double-blind, randomized order: placebo, propranolol (80 mg twice daily) and pindolol (10 mg twice daily) for 10 days, with a period of 48 to 60 hours from the initial dose to the first treadmill test and a 4-day washout period between drugs. Cardiac output was measured using the carbon dioxide rebreathing method and SV was calculated from cardiac output and heart rate as follows: SV = cardiac output/heart rate. Cardiac outputs were estimated at rest and while walking on a treadmill at 25, 45, 60 and 75% of the subject's previously determined maximal oxygen uptake (VO2max). No significant differences were found in cardiac output between either of the drugs and placebo at rest, or at any of the 4 rates of work. Propranolol significantly increased SV above placebo values (p less than 0.05) for both trained and untrained groups at the intensities of 45, 60 and 75%. Significant differences in SV were found between pindolol and placebo only at the intensities of 60 and 75% in the trained group. Contrary to expectations, SV showed no indication of a plateau with propranolol in the trained subjects throughout the 4 different exercise intensities, whereas a plateau was established under placebo conditions by 45% of VO2max in both trained and untrained subjects. These results suggest that both trained and untrained hypertensive persons can exercise with beta-adrenergic blockade at submaximal levels without compromised cardiac function.

The extent to which lipolysis is attenuated during prolonged submaximal exercise during beta blockade was determined in 12 normotensive endurance-trained and 12 hypertensive sedentary men using nonselective drugs with and without intrinsic sympathomimetic activity (ISA). Initially, subjects performed a graded treadmill test to determine maximal oxygen uptake (VO2max). This was followed by 2-hour walks at 25 and 45% of the subject's VO2max under each of 3 treatments: pindolol (ISA), propranolol (non-ISA) and placebo. The distribution of medication was randomized and double blinded. Blood samples taken at rest and every 30 minutes during the 2-hour walks were analyzed to determine the concentrations of free fatty acids (FFA) and glycerol. On the basis of the respective changes in FFA, glycerols and the respiratory exchange ratio, beta-adrenergic blockade did not attenuate lipolysis in the untrained hypertensive subjects when compared with the placebo administration. However, beta blockade did demonstrate a tendency to attenuate lipolysis in the trained, normotensive subjects when compared with results after placebo administration. This was particularly evident at 30 minutes of exercise, when both glycerol and FFA concentrations were not increased above resting values under both conditions of beta blockade. No differences between pindolol and propranolol were observed. Therefore, a beta-blocking agent with ISA properties appears to have no clear benefit with respect to lipid metabolism during low and moderate intensity exercise. Furthermore, these data demonstrate that beta blockade does not inhibit exercise-induced lipolysis at low and moderate intensities of exercise as formerly believed, and is unlikely to be the cause of fatigue normally observed during work in patient populations taking beta-blocking medication.

Aerobic exercise training is used for rehabilitation in patients with chronic obstructive pulmonary disease (COPD), although it has little effect on muscle weakness and atrophy. Resistance training may be a useful addition to aerobic programs for these patients. The purpose of the present study was to investigate the effects of resistance training in addition to aerobic training on functional outcomes in patients with COPD. Seventeen COPD patients enrolled in an aerobic-based program that met twice a week were assigned to a 12-week control/aerobic [CON: n=8; 63 (8) years; mean (SD)] or a resistance/aerobic group [RES: n=9; 61 (7) years]. RES trained an additional twice a week on 12 resistance machines, performing three sets of 8–12 repetitions at 32–64% of their one-repetition maximum (1-RM) lifts. RES (P

To investigate the influence of intensity versus total energy expenditure on neutrophilia and blood oxidative stress to acute exercise.Nine males (18-30 yr) completed one maximal (Max) and three submaximal exercise sessions: 1) 45 min at 10% above (LT+) lactate threshold (LT), 2) 45 min at 10% below (LT-) LT, and 3) 10% below LT until caloric expenditure equaled the 10%+ trial (LT-kcal). Blood was sampled before (PRE), immediately (POST), 1 h, and 2 h after exercise to measure neutrophils, myeloperoxidase, superoxide (O(2)-), neutrophil activation (O(2)-/neutrophils), ascorbic acid, uric acid, malondialdehyde, and lipid hydroperoxides.Intensity-dependent neutrophilia occurred POST exercise with significant increases (Por= 0.05) after Max and LT+. A second neutrophilia wave occurred 2 h postexercise. Superoxide was elevated POST (Max) and 2 h post (Max and LT+). In contrast, O(2)-/neutrophils was increased at 2 h only (Max and LT+). These data indicate that immediately postexercise, total neutrophil number rather than activation best represents neutrophil-generated reactive species within blood. POST Max, ascorbic acid and uric acid were decreased indicating a blood oxidative stress occurred. Alternately, total energy expenditure was not related to any marker of neutrophilia or oxidative stress.Exercise intensity plays a major role in postexercise blood oxidative stress, whereas total exercise energy expenditure does not. Further, neutrophils recruited into circulation during exercise may impose a threshold dependent oxidative stress in blood plasma after exercise.

The purpose of the study was to determine the accuracy of 11 prediction equations in estimating the 1 repetition maximum (1 RM) bench press from repetitions completed by collegiate football players (N = 69) using 225 lb. The demographic variables race, age, height, weight, fat-free weight, and percent body fat were measured to determine whether these variables increased the accuracy of the prediction equations; race was the most frequently selected variable in the regression analyses. The validity of the prediction equations was dependent upon the number of repetitions performed, i.e., validity was higher when fewer repetitions were completed. Explained variability of 1 RM was slightly higher for all 11 equations when demographic variables were included. A new prediction equation was also developed using the number of repetitions performed and the demographic variables height and fat-free weight.

Background Since the passage of The Dietary Supplement Health and Education Act in 1994, there has been a flood of new "dietary" supplements promoting anti-aging benefits such as the enhancement of growth hormone or testosterone levels. Androstenediol and androstenedione are such products. This study's purpose was to elucidate the physiological and hormonal effects of 200 mg/d of oral androstenediol and androstenedione supplementation in men aged 35 to 65 years while participating in a 12-week high-intensity resistance training program. Methods Fifty men not consuming any androgenic-enhancing substances and with normal total testosterone levels, prostate-specific antigen, hemoglobin, and hematocrit, and with no sign of cardiovascular or metabolic diseases participated. Subjects were randomly assigned to a placebo, androstenediol (diol), or androstenedione (dione) group using a double-blind study design. Main outcomes included serum sex hormone profile, body composition assessment, muscular strength, and blood lipid profiles. Results During the 12 weeks of androstenedione or androstenediol use, a significant increase in the aromatization by-products estrone and estradiol was observed in both groups ( P = .03). In the dione group, total testosterone levels significantly increased 16% after 1 month of use, but by the end of 12 weeks, they returned to pretreatment levels. This return to baseline levels resulted from increases in aromatization and down-regulation in endogenous testosterone synthesis based on the fact that luteinizing hormone was attenuated 18% to 33% during the treatment period. Neither androstenediol nor androstenedione enhanced the adaptations to resistance training compared with placebo for body composition or muscular strength. However, both androstenediol and androstenedione supplementation adversely affected high-density lipoprotein cholesterol (HDL-C) levels, coronary heart disease risk (representing a 6.5% increase), and each group's respective (low-density lipoprotein cholesterol [LDL-C]/HDL-C)/(apolipoprotein A/apolipoprotein B) lipid ratio (diol: +5.2%; dione: +10.5%; P = .05). In contrast, the placebo group's HDL-C levels increased 5.1%, with a 12.3% decline in the (LDL-C/HDL-C)/(apolipoprotein A/apolipoprotein B) lipid ratio. These negative and positive lipid effects occurred despite no significant alterations in body composition or dietary intakes in the supplemental groups or placebo group, respectively. Conclusions Testosterone precursors do not enhance adaptations to resistance training when consumed in dosages recommended by manufacturers. Testosterone precursor supplementation does result in significant increases in estrogen-related compounds, dehydroepiandrosterone sulfate concentrations, down-regulation in testosterone synthesis, and unfavorable alterations in blood lipid and coronary heart disease risk profiles of men aged 35 to 65 years.

To determine if known androgenic hormone precursors for testosterone in the androgen pathway would be readily transformed to testosterone, eight male subjects [mean age 23.8 (SEM 3) years, bodymass 83.1 (SEM 8.7) kg, height 175.6 (SEM 8.5) cm] underwent a randomized, double-blind, cross-over, placebo-controlled oral treatment with 200 mg of 4-androstene-3,17-dione (delta 4), 4-androstene-3 beta,17 beta-diol (delta 4 Diol), and placebo (PL). The periods of study were separated by 7 days of washout. Blood was drawn at baseline and subsequently every 30 min for 90 min after treatment. Analysis revealed mean area-under-the-curve (AUC) serum delta 4 concentrations to be higher during delta 4 treatment [2177 (SEM 100) nmol.l-1] than delta 4Diol [900 (SEM 96) nmol.l-1] or PL [484 (SEM 82) nmol.l-1; P0.0001]. The delta 4 treatment also revealed a significant effect on total testosterone with a mean AUC [1632.5 (SEM 121) nmol.l-1] that was greater than PL [1418.5 (SEM 131) nmol.l-1; P0.05] but not significantly different from those observed after delta 4Diol treatment [1602.9 (SEM 119) nmol.l-1; P = 0.77]. Free testosterone concentrations followed a similar pattern where mean AUC for the delta 4 treatment [6114.0 (SEM 600) pmol.l-1] was greater than after PL [4974.6 (SEM 565) pmol.l-1; P0.06] but not significantly different from those observed after delta 4Diol [5632.0 (SEM 389) pmol.l-1; P = 0.48]. The appearance and apparent conversion to total and free testosterone over 90 min was stronger for the delta 4 treatment (r = 0.91, P0.045) than for delta 4Diol treatment (r = 0.69, NS) and negatively correlated for PL (r = -0.90, P0.02). These results would suggest that delta 4, and perhaps delta 4Diol, taken by month are capable of producing in vivo increases in testosterone concentrations in apparently healthy young men as has already been observed in women after treatment with delta 4.