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The aim of this study was to examine physiological, perceptual, and affective responses during self-paced walking for three age groups. 66 adult women were assigned into three groups by age: 20–25 yr. (n=22), 30–35 yr. (n= 22), and 40–45 yr. (n= 22). Each participant completed a maximal exercise test and a 20-min. bout of walking at a self-selected pace. The preferred walking speed was similar for all age groups, whereas physiological responses relative to maximal and ventilatory threshold values were greater in the 40–45 yr. group than the other two groups. Nevertheless, perceptual and affective responses were similar for all age groups. These findings suggest that physiological responses, but not perceptual and affective responses, of sedentary women are associated with age during walking at a self-selected pace.

The aim of this study was to investigate the influence of adiposity (%body fat) on physiological, perceptual, and affective responses during walking. 45 women were divided into low, medium, and high tertiles according to %body fat. Each participant completed a maximal exercise test and a 20-min. bout of walking at a self-selected pace. The preferred walking speed was similar among groups, whereas %VO2max was greater in the high fertile group compared with the other two groups. Nevertheless, perceptual and affective responses were similar between the groups. These findings suggest that physiological responses relative to maximal capacity, but not perceptual and affective responses, of sedentary women are influenced by adiposity during walking at a self-selected pace. However, when the physiological responses are relative to ventilatory threshold, there are no differences between individuals with different levels of adiposity.

The object of this investigation was to establish a group-normalized perceptual response, using the Borg 15-category rating of perceived exertion (RPE) scale, that is consistent with the Surgeon General's recommendations for physical activity intensity. This normalized response is defined as a range of RPEs corresponding to a target physiological outcome during exercise common to a specified group of individuals. 24 college-age students (12 men; 12 women) underwent a progressive exercise test administered on a semi-recumbent leg cycle machine to estimate VO2peak and 12 6-min. exercise trials on a combined arm and leg exercise machine. Three trials were conducted per day, and at least 24 hr. separated testing sessions. RPEs between 7 and 10 were consistently estimated during trials categorized as light to moderately intense (35 to 53% VO2peak). These exercise intensities resulted in an energy expenditure of between 5.38 (SD= 1.37) to 7.56 (SD=0.60) and 3.58 (SD= 0.58) to 5.30 (SD=0.97) kcal · min.−1for these men and women, respectively. RPEs corresponding to 7: extremely light to 10: very light or light are sufficient in healthy young college students to achieve the target activity with respect to exercise intensity. Therefore, this group-normalized perceptual response, i.e., RPE = 7 to 10, may be expressed as a prescriptive reference enabling college-age individuals to produce an exercise intensity designed to promote health and studied longitudinally to assess the effects long term.

Sleep is important for athletes to recover from training and competition. However, there are no systematic reports on sleep patterns of elite soccer adult athletes. This article described the sleep pattern of elite soccer athletes and identified it is factors associated. We included only original articles, written in English, and with professional male soccer players aged over 18 years old competing in the first national division. On days without match and at a matchday, the mean of total sleep time, sleep onset latency, and sleep efficiency were less than the National Sleep Foundation's recommendation in almost all articles. Both local and match outcomes can affect the sleep pattern. So, elite soccer athletes are often unable to achieve sleep recommendations. Home matches, defeat, or a draw, as well as travels, are factors that negatively affect the quality and quantity of sleep of the athletes.

To determine the effect of endogenous opioids on catecholamine response during intense exercise [80% maximal oxygen uptake ( $$\dot V$$ O2max)], nine fit men [mean (SE) ( $$\dot V$$ O2max, 63.9 (1.7) ml · kg−1· min−1; age 27.6 (1.6) years] were studied during two treadmill exercise trials. A double-blind experimental design was used with subjects undertaking the two exercise trials in counterbalanced order. Exercise trials were 20 min in duration and were conducted 7 days apart. One exercise trial was undertaken following administration of naloxone (N; 1.2 mmol · l−1; 3 ml) and the other after receiving a placebo (P; 0.9% saline; 3 ml). Prior to each experimental trial a flexible catheter was placed into an antecubital vein and baseline blood samples were collected. Immediately afterwards, each subject received bolus injection of either N or P. Blood samples were also collected after 20 min of continuous exercise while running. Epinephrine and norepinephrine were higher (P< 0.05) in the N than P exercise trial with mean (SE) values of 1679 (196) versus 1196 (155) pmol · l−1and 24 (2.2) versus 20 (1.7) nmol · · l−1respectively. Glucose and lactate were higher (P< 0.05) in the N than P exercise trial with values of 7 (0.37) versus 5.9 (0.31) mmol · l−1and 6.9 (1.1) versus 5.3 (0.9) mmol · l−1respectively. These data suggest an opioid inhibition in the release of catecholamines during intense exercise.

To determine the effect of endogenous opioids on catecholamine response during intense exercise [80% maximal oxygen uptake ( $$\dot V$$ O2max)], nine fit men [mean (SE) ( $$\dot V$$ O2max, 63.9 (1.7) ml · kg-1 · min-1; age 27.6 (1.6) years] were studied during two treadmill exercise trials. A double-blind experimental design was used with subjects undertaking the two exercise trials in counterbalanced order. Exercise trials were 20 min in duration and were conducted 7 days apart. One exercise trial was undertaken following administration of naloxone (N; 1.2 mmol · l-1; 3 ml) and the other after receiving a placebo (P; 0.9% saline; 3 ml). Prior to each experimental trial a flexible catheter was placed into an antecubital vein and baseline blood samples were collected. Immediately afterwards, each subject received bolus injection of either N or P. Blood samples were also collected after 20 min of continuous exercise while running. Epinephrine and norepinephrine were higher (P < 0.05) in the N than P exercise trial with mean (SE) values of 1679 (196) versus 1196 (155) pmol · l-1 and 24 (2.2) versus 20 (1.7) nmol · · l-1 respectively. Glucose and lactate were higher (P < 0.05) in the N than P exercise trial with values of 7 (0.37) versus 5.9 (0.31) mmol · l-1 and 6.9 (1.1) versus 5.3 (0.9) mmol · l-1 respectively. These data suggest an opioid inhibition in the release of catecholamines during intense exercise.

Substrate utilization and glucose turnover during exercise of varying intensities in individuals with NIDDM. Med. Sci. Sports Exerc.,Vol. 31, No. 1, pp. 82-89, 1999.

This investigation examined the validity of the Borg 15-category Ratings of Perceived Exertion (RPE) scale during semirecumbent exercise in 32°C water. 9 men undertook 12 8-min. trials at 3 power outputs and 4 pedal-crank rates. The power output was distributed between the arms (20%) and legs (80%). RPEs were measured for the arms, legs, chest, and over-all body. Correlation coefficients for RPE expressed as a function of power output and gross metabolic efficiency (MEG) ranged from .56 to .83 and .54 to .70, respectively, for each pedal-crank rate. Validity coefficients were greatest at those pedal-crank rates having the highest MEG. The Borg 15-category RPE scale is valid for use during semirecumbent exercise in water.

It has been suggested that aerobic exercise influences gallstone disease pathogenesis through its effects on gallbladder motility. The purpose of the present investigation was to examine the effects of acute aerobic exercise on gallbladder emptying. Gallbladder function was evaluated, via cholescintigraphy, in 12 healthy females after undergoing two experimental trials [i.e., postprandial (P) and exercise + postprandial (E+P))]. In the E+P trial, 60 min after injection of 99mTc disofenin, subjects exercised for 30 min at 65.3 ± 0.9%, (mean ± SEM) of VO2peak on a recumbent leg ergometer, and then ingested 8 oz of a liquid meal to promote gallbladder emptying. In the P trial the meal was administered at the same time relative to the E+P trial; however, for the 30 min prior to meal ingestion subjects remained in a resting supine position. Postprandial gallbladder ejection fraction (EF) was nonsignificantly higher in the E+P trial (49.4 ± 5.1%) than in the P trial (46.6 ± 6.7%). Results of this study also indicated that during a fasted state the gallbladder undergoes significant periods of spontaneous emptying both at rest EF = 25± 5.6% (P< 0.02) and during exercise EF = 17 ± 4.3% (P< 0.01). In conclusion, the results of this study indicate that 30 min of aerobic exercise at 65% of VO2peak does not effect gallbladder motility in a healthy, premenopausal, female population.

ROBERTSON, R., F. GOSS, T. MICHAEL, N. MOYNA, P. GORDON, P. VISICH, J. KANG, T. ANGELOPOULOS, S. DASILVA, and K. METZ. Metabolic and perceptual responses during arm and leg ergometry in water and air. Med. Sci. Sports Exerc., Vol. 27, No. 5, pp. 760–764, 1995. This investigation determined metabolic (i.e., kcal·min-1) responses and ratings of perceived exertion (RPE) for varying pedal-crank rates (PCR) and power outputs (PO) during arm and leg exercise in thermoneutral air (TA) and water (TW). Nine males (age 28.2 yr; leg cycle VO2peak3.41·min-1) undertook the 24 exercise trials. During the TW trials kcal·min-1were less (P< 0.05): at 50 W for 40 (X ± SB; 10.9 ± 0.8) than 50 (8.2 ± 0.2), 60 (8.2 ± 0.6), or 70 (7.4 ± 0.3) rev·min-1and at 100 W for 40 (15.2 ± 0.7), 50 (14.0 ± 1.1), and 60 (13.8 ± 0.7) than 70 (12.1 ± 0.5) rev·min-1. All other comparisons of kcal·min-1between PCR at the three PO were not significant. During the TA trials kcal·min-1were less (P< 0.05): at 50 W for 40 (11.4 ± 0.3) than 60 (9.7 ± 0.4) and 70 (9.1 ± 0.4) rev·min-1and for 50 (11.0 ± 0.5) than 70 rev·min-1. During the TW trials: RPE-Arms and RPE-Overall at 50 W were lower (P< 0.05) for 40 (8.1 ± 0.5; 8.3 ± 0.4) than 60 (9.6 ± 0.5; 9.8 ± 0.6) and 70 (9.3 ± 0.5; 9.9 ± 0.7) rev·min-1, RPE-Legs at 50 W was lower (P< 0.05) for 40 (8,3 ± 0.4) than 70 (9.9 ± 0.7) rev·min-1. All other comparisons of RPE between PCR at the three PO were not significant.

This study was conducted to compare gross efficiency (GE), net efficiency(NE), work efficiency (WE), and delta efficiency (DE) between arm crank and cycle exercise at the same relative intensities. Eight college-aged males underwent two experimental trials presented in a randomized counterbalanced order. During each trial subjects performed three intermittent 7-min exercise bouts separated by 10-min rest intervals on an arm or semirecumbent leg ergometer. The power outputs for the three bouts of arm crank or cycle exercise corresponded to 50, 60, and 70% of the mode-specificVO2peak. GE, NE, and WE were determined as the ratio of Kcal·min-1equivalent of power output to Kcal·min-1of total energy expended, energy expended above rest and energy expended above unloaded exercise, respectively. DE was determined as the ratio of the increment of Kcal·min-1of power output above the previous lower intensity to the increment of Kcal·min-1of total energy expended above the previous lower intensity. GE and NE did not differ between arm crank and cycle exercises. However, WE was lower (P< 0.05) during arm crank than cycle exercise at 50, 60, and 70% VO2peak. DE was also lower(P< 0.05) during arm crank than cycle exercise at Δ 50-60 and at Δ 60-70% VO2peak. It is concluded metabolic efficiency as determined by work and delta efficiency indices was lower during arm crank compared with cycle exercise at the same relative intensities. These findings add to the understanding of the difference in metabolic efficiency between upper and lower body exercise.

This investigation examined the effect of carbohydrate substrate availability on ratings of perceived exertion (RPE) during cycling at moderate intensity to exhaustion and the relation between submaximal endurance performance and RPE obtained following 2 hr. of cycling at moderate intensity. Seven male cyclists performed two exercise trials at power output corresponding to 70% of their peak oxygen uptake until exhaustion. Subjects ingested either a 6% glucose/sucrose solution at the rate of 0.6 g · kg−1(Body Weight) · hr.−1or an equal volume of artificially flavored placebo every 20 min. throughout the exercise trials. RPE for the legs, chest, and over-all body, and oxygen consumption, expired ventilation, carbohydrate oxidation rate, and blood concentrations of glucose, glycerol, and lactate were measured every 20 min. throughout exercise and at exercise termination. Statistical analysis of these dependent variables indicates that (1) an exercise-induced decrease in blood-borne carbohydrate substrate intensifies leg and over-all perceptions of exertion during the later stages of prolonged cycling at 70% VO2peak. (2) Factors other than availability of blood-borne carbohydrate substrate may influence perceptual intensity at exhaustion. (3) Ratings of perceived exertion for the legs and over-all body obtained after 2 hr. of cycling at moderate intensity may be useful in predicting submaximal endurance performance.