SEARCH · PubMed Health

Results for “physical performance”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

PubMed2005

The effect of hormone replacement on physical performance in community-dwelling elderly women.

PURPOSE: Our aim was to determine the effect of hormone replacement on physical performance measures, functional ability, physical activity, falls, and cognitive function in elderly women. SUBJECTS AND METHODS: Following a 3-month, open-label, run-in phase, we randomized 373 community-dwelling women aged 65 years and older to receive conjugated equine estrogen 0.625 mg/day plus or minus medroxyprogesterone 2.5 mg/day vs placebo for 3 years in a double-blind fashion. We assessed time to rise from a chair, timed walking, balance, Instrumental Activities of Daily Living, Physical Activity Scale of the Elderly, Folstein Mini-Mental State Examination, and falls. RESULTS: Over 3 years, except for balance scores, performance measures declined significantly (all P<.05). There were no significant mean differences between women on hormone replacement versus placebo for rising time (0.1, -0.5 to 0.7 seconds [mean, 95% confidence interval]), walking normal (0.0, -0.4 to 0.4 seconds), and walking fast (0.2, -0.1 to 0.6 seconds). There were no significant mean differences between the two groups for the Instrumental Activities of Daily Living (0.1, -0.1 to 0.3 points), Physical Activity Scale of the Elderly (-3, -15 to 8 points), Folstein Mini-Mental State Examination (-0.1, -0.3 to 0.3 points), or the proportion of participants reporting falls (-1, -11 to 9%). CONCLUSION: In elderly women, hormone replacement had no statistically significant effect on cognition or balance, nor did it prevent the age-related decline in physical measures of mobility, ability to rise from a chair, self-reported activities of daily living, physical activity scores, or falls.

Accidental Falls↗

PubMed1994

Iron-deficiency anaemia and physical performance in adolescent girls from different ethnic backgrounds.

One hundred and fourteen 11-14-year-old schoolgirls from Wembley, Middlesex, were assessed for Fe status (haemoglobin (Hb), packed cell volume and mean corpuscular Hb concentration, height, weight, eating habits, and ethnic origin, and undertook a step test to assess physical performance. Overall, 20% of girls had Hb less than 120 g/l, ranging from 11% in White girls to 22-25% in girls of Asian origin. Prevalence of low Hb was 20% in vegetarians, higher in White vegetarians compared with non-vegetarians (23 v. 4%), but lower in the Indian vegetarians compared with non-vegetarians (17 v. 32%). Low Hb was present in 25% of girls who had tried to lose weight in the previous year, and was more common in girls from manual social class backgrounds than non-manual (24 v. 10%). At the start of the step test the twenty-three girls with low Hb had heart rates similar to those with normal Hb, but heart rates in the low Hb group were significantly elevated immediately after the step test, and still significantly elevated 1 min later. The present results confirm the findings of a previous study in White girls, and suggest that physical performance may be compromised at mild levels of anaemia.

Adolescent↗

PubMed1993

Physical performance of the Siemens MultiSPECT 3 gamma camera.

We evaluated physical performance of the new Siemens MultiSPECT 3 gamma camera. The camera is a triple-headed, large detector system dedicated to multislice single photon emission tomographic (SPET) imaging over all the human body. A triangular aperture up to 60 cm in diameter and a patient couch with low gamma-ray attenuation allow all patients to be studied without exception. The patient is easily, quickly and reproducibly positioned. Collimator change is rapidly and semiautomatically performed. Camera tuning, calibration, acquisition and processing are controlled by a MacIntosh Quadra 950 computer. The ICON software is easy to use (a mouse driven system) and the operator does not necessarily need to go through the manuals. The software includes useful reporting and imaging utilities but the version tested by us (vol. 3.0) also has several limitations such as no gated or dynamic SPET, no list-mode acquisition and no body outline attenuation correction. The planar sensitivity using high-resolution collimators (HR) is 380 cps MBq-1 for 99Tcm with a symmetric energy window of 15%. The radial SPET resolution is 8.5 mm full-width half-maximum (FWHM) in scatter with a rotational radius of 12.6 cm (corresponding to the radius of a brain scan) and a tangential resolution of 7.1 mm. The quality of the daily bone, brain and heart scans is superior when compared to those of a conventional single-headed gamma camera. The system allows fast and accurate SPET imaging both for clinical routine practice and for research.

Adult↗

PubMed2003

Effects of androgen replacement on metabolism and physical performances in male hypogonadism.

Hypogonadism in men is associated with decreased physical performance. This phenomenon depends on significantly measurable adverse traits in body composition, namely increased body fat content and reduced muscle mass. Physical abilities in hypogonadal men are further hampered by lower oxygen supply due to decreased hemoglobin concentrations and by poor glucose utilization. In addition, dysthymia and lack of necessary aggressiveness contribute to further deterioration of physical features. T substitution can improve lipid and insulin metabolism, resuiting in changes of body composition, such as decreasing fat depots. Growth of muscle fibers can also be observed. Stabilization of the musculo-skeletal system by increased bone density will further contribute to increased physical fitness, reflected by increased strength and endurance. Treatment outcome is strongly influenced by age and training. The issues reviewed strongly support T treatment of hypogonadal men accompanied by regular monitoring.

Body Composition↗

PubMed1981

[Correlations between the components of the test for the evaluation of physical performance II of the Canadian Association of Health, Physical Education and Recreation].

The Fitness-Performance Tests developed in 1965 by the Canadian Association for Health, Physical Education and Recreation have been criticized with regard to the validity of the 300 yard run as an endurance measure and with regard to the redundance of some items involving lower limb performance. The purposes of this study were to identify a more appropriate endurance performance test item and to analyze the inter-dependence of the items which utilize leg power in their performance. A sample of 9000 young Canadians aged 6 to 17 years, was randomly selected from the 10 provinces and the 2 territories. Correlation coefficients were calculated between: standing long jump, the 50 m. run, and the endurance run (800 m. for 6-9 years, 1600 m. for 10-12 years and 2400 m. for 13-17 years). Among the different age and sex groups, the correlations between the endurance run and the 50 m. run varied from 0.40 to 0.49. The correlations between standing long jump, the agility run (4 x 10 m.) and the 50 m. run were from 0.69 to 0.83 for all the boys and girls. The correlations between these three items are even lower when performances are analyzed by age and sex groups. The highest variations are mainly in the preadolescent period for both sexes.

Adolescent↗

PubMed2003

Hyperandrogenicity is an alternative mechanism underlying oligomenorrhea or amenorrhea in female athletes and may improve physical performance.

OBJECTIVE: To evaluate endocrine mechanisms underlying oligomenorrhea or amenorrhea in female athletes. DESIGN: Cross-sectional study. SETTING: Women's health clinical research unit at a university hospital. PATIENT(S): Age- and BMI-matched groups of athletes active in endurance sports with and without menstrual disturbances and regularly cycling sedentary controls. INTERVENTION(S): Groups were compared with respect to endocrine status, body composition, and physical performance. MAIN OUTCOME MEASURE(S): Identification of a subgroup of oligomenorrheic or amenorrheic athletes with increased androgen levels and anabolic body composition. RESULT(S): A subgroup of 8 of 25 athletes with menstrual disturbances had significantly higher serum levels of free and total testosterone, androstenedione, LH-FSH ratio, and lower SHBG levels than did all other groups. Other oligomenorrheic or amenorrheic athletes had normal values comparable to those in regularly menstruating athletes and controls. The hyperandrogenic subgroup showed a more anabolic body composition, with higher total bone mineral density and upper-lower fat mass ratio than did oligomenorrheic or amenorrheic athletes with normal androgen levels. The hyperandrogenic subgroup had the highest VO2 max and the highest performance values in general. CONCLUSION(S): Menstrual disturbances in female athletes are often explained as a consequence of hypothalamic inhibition and caloric deficiency. We suggest that essential hyperandrogenism is an alternative mechanism underlying oligomenorrhea or amenorrhea in some female athletes and may imply an advantage for physical performance.

Adult↗

PubMed1989

Specificity of endurance, sprint and strength training on physical performance capacity in young athletes.

Three prebubescent athlete groups of endurance runners (E; n = 4), sprinters (S; n = 4) and weightlifters (WL; n = 4) and one control group (C; n = 6) as well as one junior but postpubescent weightlifter group (JWL; n = 6) volunteered as subjects in order to investigate specific effects of endurance, sprint and strength training on physical performance capacity during a 1 year follow-up period. The prepubescent E-group had higher (p less than 0.05) VO2 max (66.5 +/- 2.9 ml x kg1 x min-1) already at the beginning of the study than the other three groups. The prepubescent WL-group demonstrated greater (p less than 0.05) maximal muscular strength than the E-group and the WL-group increased its strength greatly by 21.4% (p less than 0.05) during the follow-up. No significant differences were observed in physical performance capacity between the prepubescent WL- and S-groups. Both groups demonstrated a slightly (ns.) better force-time curve recorded from the leg extensor muscles than the E-group and significant (p less than 0.05) increases occurred in these two groups in dynamic explosive performance during the follow-up. The postpubescent JWL-group demonstrated much greater (p less than 0.001) muscular mass and maximal strength than the prepubescent groups. No significant changes occurred in explosive types of performances in these athletes but significant (p less than 0.05) increase took place in the maximal neural activation and strength of the leg extensor muscles during the 1 year.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1987

Effects on physical performance of intrinsic sympathomimetic activity (ISA) during selective beta 1-blockade.

In 15 healthy, not specifically trained volunteers (age: 26.6 +/- 2.7 years) single equipotent doses of a selective beta 1-blocker with intrinsic sympathomimetic activity (ISA) (200 mg Epanolol-Visacor; V) and of a selective beta 1-blocker without ISA (100 mg Metoprolol; M) were compared with placebo (P) with respect to their influence upon physical performance capacity and metabolism in a random, double blind, cross-over experimental setting. The subjects underwent three step by step incremental treadmill tests and three treadmill endurance tests until volitional exhaustion. Maximum running speed and maximum oxygen uptake were used as measures of maximum performance capacity. Running speed and oxygen uptake related to individual anaerobic threshold, and running time and running distance in the endurance tests were used as measures of endurance capacity. Both maximum and endurance performances were reduced significantly by beta-blockade. No relevant differences were discerned between V and M. The uniform reduction in exercise heart rate with both beta-blockers demonstrated the application of equipotent doses. At rest, heart rate was significantly higher under V than under M. Carbohydrate metabolism was unaffected, both beta-blockers showing equal inhibition of lipolysis during exercise. We conclude that intrinsic sympathomimetic activity has no influence upon physical performance and metabolism during selective beta 1-blockade.

Adrenergic beta-Antagonists↗

PubMed1994

Effects of moderate energy restriction on physical performance and substrate utilization in non-obese men.

Energy restriction (ER) has shown to be an effective 'anti-aging' factor in rodents, resulting in an increased life span and preventing or delaying the occurrence of many age-related diseases in rodents. As a part of a feasibility study on the potential application of ER in humans, we studied the effects of moderate ER on physical performance in 24 apparently healthy, non-obese middle-aged men. After two weeks of weight maintenance the ER group (n = 16) received 80% of their habitual energy intake, while a control group (n = 8) still received their weight-maintaining diet for ten weeks. Physical performance (bicycle ergometer) was estimated by a maximal (until exhaustion) and a submaximal (30 min at 60% of VO2max) exercise test. After the experimental period the subjects in ER group had a significantly shorter cycling time (delta = 1.31 +/- 1.14 vs -0.45 +/- 1.56 min, p = 0.01), and thus had a lower maximal power output (delta = 4.3 +/- 5.9 vs -6.3 +/- 13.6 watt, p < 0.05) and maximal oxygen uptake (delta = 0.03 +/- 0.18 vs -0.18 +/- 0.321/min, p = 0.05) during the maximal exercise test, than the subjects in the control group. None of these changes correlated with weight loss. As in every exercise test, motivation could have played an important role. During the submaximal exercise test no significant changes between the two groups in HR, VO2, RER and FFA, glucose, lactate and catecholamine levels were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1977

[Physical performance in patients with focal infection ergospirometric stress-testing before and after tonsillectomy (author's transl)].

The diagnosis of a focal infection in 13 patients (6 men and 7 women, aged 18 to 36) was based on the findings of chronic tonsillitis and general complaints interpreted as focal symptoms. The patients underwent symptom-limited maximal stress-testing before and after tonsillectomy to rule out any impairment of physical performance on the basis of computer-assisted processing of ergospirometric data. It can be concluded that the actual data of maximal oxygen uptake (aerobic power), the phenomenon of adaptation to increasing work loads (derived from rating of the increase in oxygen uptake during rectangular-triangular bicycle ergometry), the on-line processed index of anaerobic power and the anaerobic threshold, as well as heart rate and arterial blood pressure regulation did not differ in these patients from findings in healthy subjects. Nor were these parameters altered by tonsillectomy. Tonsillar focal infection is unlikely to cause any impairment of physical performance with respect to parameters of cardio-respiratory and metabolic function.

Adaptation, Physiological↗

PubMed2005

Reliability of simple portable tests of physical performance in older people after hip fracture.

OBJECTIVE: To investigate the test-retest reliability of measures of strength, balance, gait and functional performance when used with older people following hip fracture. SUBJECTS: Thirty people (16 hospital inpatients and 14 community dwellers). DESIGN: Subjects underwent two assessments: one day apart for the hospital inpatients and one week apart for the community dwellers. MEASUREMENT: Strength (dynamometer, sphygmomanometer, spring balance, lateral step-up ability), balance (sway-meter, Functional Reach Test, single leg stance time, Step Test), gait (timed 6-m walk with steps taken, base of support and step length), and functional performance (PPME total score and timed supine-to-sit and sit-to-stand) were measured. RESULTS: Eleven of the 14 continuously scaled measurement tools achieved excellent reliability (intraclass correlation coefficient (ICC) > 0.75) for one or more tests. A hand-held dynamometer was found to be the tool with the highest test-retest reliability for measuring hip muscle strength (ICC (3,1) 0.86 for affected hip abduction). For measurement of knee extension strength, a spring balance (ICC (3,1) 0.94 affected leg) was the most reliable. For testing balance, the Step Test (ICC (3,1) 0.94 for stepping with affected leg) and Functional Reach Test (ICC (3,1) 0.89) had the highest test-retest reliability. The ICC (3,1) values were 0.97 for walking velocity (comfortable pace) and 0.96 for the total score of the Physical Performance and Mobility Examination. CONCLUSION: The test-retest reliability of a number of simple measures of physical performance is excellent when used with this population.

Aged↗

PubMed1999

Effects of growth hormone replacement on physical performance and body composition in GH deficient adults.

OBJECTIVES: Adults with GH deficiency complain frequently of low energy levels resulting in a low perceived quality of life. Body composition is altered, with increased fat mass and decreased lean body mass, and muscle strength is reduced. The aims of this study were to determine the effects of GH replacement on physical performance and body composition in GH deficient (GHD) adults. STUDY DESIGN: The study consisted of a 6-month randomised, double-blind, placebo controlled study of the administration of GH (0.25 IU/Kg/week (0.125 IU/kg/week for the first four weeks)) followed by a 6-month open phase of GH therapy. PATIENTS: Thirty-five GHD adults (17F), mean age 39.8 years (range 21.1-59.9), on conventional replacement therapy as required. METHODS: Maximum aerobic capacity was measured using an incremental walking test to volitional exhaustion on a motorized treadmill. Quadriceps muscle strength was assessed by measuring maximum voluntary contractions and body composition by dual energy X-ray absorptiometry (DEXA). RESULTS: There were no statistically significant changes in quadriceps muscle strength between the GH and placebo groups. In both groups, there was a significant increase in quadriceps muscle strength compared to baseline during the double-blind period (GH group: P = 0.016; placebo group: P = 0.048). Compared to baseline, muscle strength was further improved in the GH treatment group after 12 months of treatment (P = 0.007). No further improvement was noted in the placebo group after 6 months on open GH treatment. In the placebo group, maximum aerobic capacity decreased during the placebo period (P = 0.017). No significant change was observed in the GH group. During open GH treatment the previously placebo treated group had a significant increase of maximum aerobic capacity (P < 0.049) whereas no significant improvement could be seen in the GH group. In the GH group there was a significant increase in lean body mass (P = 0.001) and a significant decrease in fat mass (P < 0.001). No statistically significant changes were noted in the placebo group: the differences in these changes between treatment groups were statistically significant (lean body mass: P = 0.009; fat mass: P < 0.001). The changes in body composition in the GH group during the 6 month placebo-controlled period were maintained during continued open treatment. Similar changes in body composition to those observed in the GH group during the 6 month placebo-controlled period were also seen in the placebo group once the patients received GH treatment. CONCLUSIONS: Our data show that GH replacement in GH deficient adults is associated with favourable changes in body composition, which could be important in the long term health outcome and physical activity of GH deficient patients. Our data support the concept that GH therapy alone, in the absence of some form of exercise programme, may increase the amount of lean tissue but not the quality or functional capacity of this tissue and it may be that training, in addition to GH therapy, may be necessary to significantly increase physical performance in these patients. We suggest that future trials with GH therapy and general approaches to the treatment of GH deficiency should include a planned activity programme as an approach to health improvement in these patients.

Absorptiometry, Photon↗

PubMed1996

Health and physical performance of elderly Europeans. SENECA Investigators.

OBJECTIVE: To assess four-year changes in different measures of health, functional limitations and activities of daily living occurring in elderly Europeans who participated in the SENECA surveys of 1988/89 and 1993. METHODS: Similar questions on self-perceived health, chronic diseases, drug intake and activities of daily living (ADL) were asked in a standardized way in 1988/89 and in 1993. In 1993 an objective test of physical performance (PPT) was added. SETTING: Nineteen towns in 12 European countries were surveyed in 1988/89; 1282 men and 1304 women born between 1913 and 1918 participated in SENECA's baseline study. Nine of the towns participated in the follow-up study in 1993 and four new localities joined. SUBJECTS: Data on health and physical performance are presented for 571 men and 603 women from nine towns in Europe who took part in both SENECA studies and, additionally for 105 men and 156 women from the four localities examined in 1993 only. RESULTS: Of the 571 men and 603 women examined at both baseline and follow-up, 54% of the men and 37% of the women could do all mobility and selfcare items of daily living in 1988/89 without difficulty or help. In 1993, only 40% of the men and 22% of the women could do so, i.e. on balance 63 fewer men and 72 fewer women than in 1988. There was much less variation between towns in simple function tests than in the basic ADL actions. The PPT (sum score) was on average 20.8 in men and 20.3 in women, ranging from 14.8 to 22.8 across towns. Over the four-year period, the proportion perceiving their health to be excellent or good decreased, but the changes differed considerably from one town to another. At follow-up, 68% of the men and 78% of the women had at least one chronic disease; the average number of diseases for each participant in the total SENECA population being 1.1. The range in prevalence of chronic diseases varied from 40% in Spanish men to 100% in Portuguese women. Although there was no significant increase in the number of participants reporting chronic disease, the number of chronic diseases per participant increased from 0.9 to 1.0 in men and from 1.1 to 1.3 in women. CONCLUSIONS: During the period from 1988/89 to 1993 the proportion of ADL-independent men and women decreased by 25% and the number of people perceiving their health to be poor increased by 21%, but there was no change in the prevalence of chronic diseases.

Activities of Daily Living↗

PubMed2002

Effects of montelukast on physical performance and exercise economy in adult asthmatics with exercise-induced bronchoconstriction.

Leukotriene antagonists are effective in the treatment of exercise-induced bronchoconstriction. Montelukast is a specific cysteinyl-leukotriene receptor1 antagonist without known effects on the pulmonary vessels, which in theory should be advantageous with respect to gas exchange. In addition to lung function, we investigated the effects of montelukast on parameters of gas exchange and physical performance in 16 asthmatics with exercise-induced bronchoconstriction in a double-blind cross-over placebo-controlled study. Subjects were tested at an ambient temperature of -15 degrees C with a tread mill exercise protocol consisting of consecutive workloads of 80% V'O(2max) (6 min), rest (4 min), 60% V'O(2max) (6 min) and step increments of exercise until exhaustion. Montelukast reduced the maximum post-exercise fall in FEV1 (P < 0.01), improved the running time to exhaustion in 11 of 16 test subjects (one unchanged) (P = 0.03), and reduced the Borg score at exhaustion (P = 0.03) and the breathing frequency after 3 min at 60% V'O(2max) (P = 0.03). V'(O2), V'CO(2), minute ventilation, ventilatory equivalents, respiratory exchange ratio, heart rate and oxygen pulse were not significantly different after montelukast and placebo. We conclude that montelukast has a beneficial effect on physical performance in most adults with exercise-induced asthma without any observed effect on gas-exchange parameters.

Acetates↗

PubMed2001

Angiotensin-converting enzyme genotype and physical performance during US Army basic training.

Prior studies have suggested that angiotensin I-converting enzyme (ACE) genotype correlates with superior physical performance in highly selected populations. This study assessed whether such an association exists in a heterogeneous population. Using polymerase chain reaction techniques, we determined the ACE genotypes (insertion/insertion, deletion/insertion, or deletion/deletion) of 62 male and 85 female US Army recruits. Before and after 8 wk of basic training, we determined peak oxygen uptake and performance on the Army Physical Fitness Test (APFT), which includes standardized measures of muscular endurance (sit-ups, push-ups) and a 2-mile run. Subjects of different ACE genotypes had similar peak oxygen uptakes and APFT scores, both before and after training. Subjects with genotype II had higher APFT scores than others, but the differences were not statistically significant. Furthermore, no ACE genotype group had a performance advantage in analyses that adjusted for baseline fitness. We conclude that ACE genotype does not have a strong effect on aerobic power or muscular endurance in healthy, young American adults drawn from an ethnically and geographically diverse population.

Adult↗

PubMed2000

Cross-sectional and prospective relationships of interleukin-6 and C-reactive protein with physical performance in elderly persons: MacArthur studies of successful aging.

BACKGROUND: Chronic inflammation has been proposed as a biological mechanism underlying the decline in physical function that occurs with aging. The purpose of this investigation was to examine the cross-sectional and prospective relationships between markers of inflammation, interleukin-6 (IL-6) and C-reactive protein (CRP), with several measures of physical performance in older persons aged 70 to 79 years. METHODS: Subjects were 880 high-functioning men and women participating in the MacArthur Study of Successful Aging (n = 1189), a subset of the Established Populations for Epidemiologic Studies of the Elderly (n = 4030). Plasma IL-6 and CRP levels were determined by enzyme-linked immunosorbent assay and log transformed to normalize the distributions. Physical function measures included handgrip strength, signature time, chair stands (time to complete five repetitions), and 6-m walk time. RESULTS: Women had lower (p < .05) IL-6 levels than men, but there was no significant difference between blacks and whites. IL-6 and CRP levels were higher (p < .05) in current smokers than in nonsmokers and in those with a greater body mass index (BMI). Hours per year undertaking moderate and strenuous physical activity were also related to inflammatory markers with higher (p < .001) IL-6 and CRP levels in less active individuals. After adjusting for age, sex, race, BMI, smoking status, use of nonsteroidal anti-inflammatory drugs, and prevalence of morbidity, those in the top two quartiles for walking speed had lower (p = .012) IL-6 levels than those in the bottom quartile. In addition, there was a trend (p = .038) for lower CRP levels in those with higher walking speed. CRP levels were also lower (p = .04) in individuals in the top quartile for grip strength. No significant differences were noted for chair stands or signature time performance. Repeat performance measures obtained on 405 subjects (67% of those eligible at baseline) obtained 7 years later had declined significantly (grip strength, 18%; signature time, 21%; walking speed, 31%; p < .001), except for the chair rise; however, baseline IL-6 and CRP were not associated with a change in performance. However, those who died or who were unable to undergo testing had higher baseline IL-6 and CRP levels (p < .01) and slower walking speed (p < .05). CONCLUSIONS: Although IL-6 has been shown to predict onset of disability in older persons and both IL-6 and CRP are associated with mortality risk, these markers of inflammation have only limited associations with physical performance, except for walking measures and grip strength at baseline, and do not predict change in performance 7 years later in a high-functioning subset of older adults.

Aged↗

PubMed1991

Improved physical performance after treatment of renal anemia with recombinant human erythropoietin.

The physical performance of 12 anemic patients on renal dialysis was investigated following treatment of renal anemia with recombinant human erythropoietin (rhEPO; 40-120 U/kg, 3 times a week). Exercise intensity at a heart rate of 130 beats/min (PWC130) on a bicycle ergometer was assessed before rhEPO treatment, after reaching the target hematocrit (73 +/- 18 days), and in the maintenance phase (211 +/- 53 days). Hemoglobin concentrations measured at these time points were 7.3 +/- 1.2, 11.9 +/- 1.5, and 12.1 +/- 1.4 g/dl, respectively. PWC130 rose from 77 +/- 27 to 104 +/- 37 and 104 +/- 51 W, respectively. Aerobic threshold (i.e. blood lactic acid concentration of 2 mmol/l) shifted to higher workloads indicating improved muscle oxygen supply.

Adult↗

PubMed2006

The relationship between peak height velocity and physical performance in youth soccer players.

Longitudinal changes in height, weight and physical performance were studied in 33 Flemish male youth soccer players from the Ghent Youth Soccer Project. The players' ages at the start of the study ranged from 10.4 to 13.7 years, with a mean age of 12.2 +/- 0.7 years. Longitudinal changes were studied over a 5 year period. Peak height velocity and peak weight velocity were determined using non-smoothed polynomials. The estimations of peak height velocity, peak weight velocity and age at peak height velocity were 9.7 +/- 1.5 cm x year-1, 8.4 +/- 3.0 kg x year-1 and 13.8 +/- 0.8 years, respectively. Peak weight velocity occurred, on average, at the same age as peak height velocity. Balance, speed of limb movement, trunk strength, upper-body muscular endurance, explosive strength, running speed and agility, cardiorespiratory endurance and anaerobic capacity showed peak development at peak height velocity. A plateau in the velocity curves was observed after peak height velocity for upper-body muscular endurance, explosive strength and running speed. Flexibility exhibited peak development during the tear after peak height velocity. Trainers and coaches should be aware of the individual characteristics of the adolescent growth spurt and the training load should also be individualized at this time.

Acceleration↗