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Purpose: We examined the effect of altitude up to 5200 m on marathon (42,195 m) performances. Methods: Eight elite and four good runners participated in a marathon at 4300-m altitude (A1), and five elite runners participated both in A1 and in a marathon at 5200-m altitude (A2). The maximal aerobic power (JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2max) was determined indirectly in altitude during A1 and A2 expeditions from the scores of a 12-min running test. The fractions of JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2max utilized during both races were calculated from the linear relationship between running speed and JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2 described by Costill and Fox (1969). Results: JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2max significantly decreases with altitude (P 0.05). Conclusions: Marathon performance in altitude is mainly affected by the lower JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2max. The better performance of elite marathoners in altitude compared with good runners was related to the higher % of JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2max maintained during every marathon. The differences between the expected and the observed performances at high altitude depend on the uneven running path and on a poorer economy of running that is related to the higher mechanical work of breathing. The fractional utilization of JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2max seems lowered by acute exposure to altitude and slightly increases with acclimatization.

Skyscraper running is here analyzed in terms of mechanical and metabolic requirements, both at the general and at the individual level. Skyscraper runners' metabolic profile has been inferred from the total mechanical power estimated in 36 world records (48-421 m tall buildings), ranked by gender and age range. Individual athlete's performance (n=13) has been experimentally investigated during the Pirelli Vertical Sprint, with data loggers for altitude and heart rate (HR). At a general level, a non-linear regression of Wilkie's model relating maximal mechanical power to event duration revealed the gender and age differences in terms of maximum aerobic power and anaerobic energy resources particularly needed at the beginning of the race. The total mechanical power was found to be partitioned among: the fraction devolved to raise the body center of mass , the need to accelerate the limbs with respect to the body , and running in turns between flights of stairs . At the individual level, experiments revealed that these athletes show a metabolic profile similar to middle-distance runners. Furthermore, best skyscraper runners maintain a constant vertical speed and HR throughout the race, while others suddenly decelerate, negatively affecting the race performance.

The costs of walking (Cw) and running (Cr) were measured on 10 runners on a treadmill inclined between −0.45 to +0.45 at different speeds. The minimum Cw was 1.64 ± 0.50 J · kg−1· m−1at a 1.0 ± 0.3 m/s speed on the level. It increased on positive slopes, attained 17.33 ± 1.11 J · kg−1· m−1at +0.45, and was reduced to 0.81 ± 0.37 J · kg−1· m−1at −0.10. At steeper slopes, it increased to reach 3.46 ± 0.95 J · kg−1· m−1at −0.45. Cr was 3.40 ± 0.24 J · kg−1· m−1on the level, independent of speed. It increased on positive slopes, attained 18.93 ± 1.74 J · kg−1· m−1at +0.45, and was reduced to 1.73 ± 0.36 J · kg−1· m−1at −0.20. At steeper slopes, it increased to reach 3.92 ± 0.81 J · kg−1· m−1at −0.45. The mechanical efficiencies of walking and running above +0.15 and below −0.15 attained those of concentric and eccentric muscular contraction, respectively. The optimum gradients for mountain paths approximated 0.20–0.30 for both gaits. Downhill, Cr was some 40% lower than reported in the literature for sedentary subjects. The estimated maximum running speeds on positive gradients corresponded to those adopted in uphill races; on negative gradients they were well above those attained in downhill competitions.

A single-blind, cross-over study was carried out to evaluate the effects of acetylsalicylic acid (ASA) on cardiorespiratory performance during exercise. Eighteen young men, 9 athletes and 9 untrained but active subjects, performed a progressive maximal exercise test on a cycle ergometer (30 watt, 3 min steps, starting at 60 watt) on three different occasions, after a single administration of plain aspirin (1000mg of ASA), chewable buffered aspirin (1000mg of ASA and 600 mg of calcium carbonate) and placebo. Continuous measurement of breath-by-breath ventilation, oxygen consumption, carbon dioxide output, respiratory frequency and heart rate was carried-out at rest and during the exercise test. Blood lactate concentration was measured just before the start of exercise and at the third minute of each step in order to detect the anaerobic threshold. The pharmacokinetics of aspirin during exercise was also investigated in ten of the eighteen participants. The analysis of all investigated variables did not show any statistically significant difference between treatments, suggesting that a single dose of 1000mg of aspirin does not affect physical performance during submaximal and maximal exercise.

The effects of heavy resistance training and jumping exercise were examined during the 1989–1990 season in 12 international level alpine skiers. The athletes were tested before, during, immediately after training and during the period off training (June, July, October 1989, April 1990). Their mechanical behaviour was investigated using firstly squat jumps performed without (SJ) or with low extra loads (20 kg, SJ20kg) and high extra loads (equivalent to body mass on the shoulders, SJbm) and secondly 15–30 s continuous jumping. These tests allowed the assessment of explosive dynamic strength production (SJ and SJ20kg), slow dynamic strength (SJbm) and maximal mechanical power (continuous jumping). The training adopted resulted in specific changes in neuromuscular performance; in fact all the variables studied showed a significant improvement (P

Partial rupture of the pectoralis major muscle is quite a rare event in sports traumatology and information about its treatment is lacking in literature. In this paper the long term effect of conservative non-surgical treatment in two body-builders and one shot-putter is discussed, who reported the partial rupture while performing bench lifts with barbells. Functional recovery was evaluated a few years after the injury (from 4 to 7) with an isokinetic dynamometer (Cybex II, Lumex INC N.Y.), measuring maximal shoulder adduction-abduction torques at different angular speeds (60, 180, and 300 degrees/s). The results were compared with those of five healthy athletes practicing either body-building or weight-lifting. From the present study we conclude the following: the non-invasive treatment of a partial rupture of the pectoralis major muscle may produce almost complete functional recovery; in normal subjects adduction muscles are advantageous in comparison to the abduction ones.

Four male subjects aged 23–34 years were studied during 60 days of unilateral strength training and 40 days of detraining. Training was carried out four times a week and consisted of six series of ten maximal isokinetic knee extensions at an angular velocity of 2.09 rad·s−1. At the start and at every 20th day of training and detraining, isometric maximal voluntary contraction (MVC), integrated electromyographic activity (iEMG) and quadriceps muscle cross-sectional area (CSA) assessed at seven fractions of femur length (Lf), by nuclear magnetic resonance imaging, were measured on both trained (T) and untrained (UT) legs. Isokinetic torques at 30° before full knee extension were measured before and at the end of training at: 0, 1.05, 2.09, 3.14, 4.19, 5.24 rad·s−1. After 60 days T leg CSA had increased by 8.5%±1.4% (mean±SEM,n=4,p

In these studies the anthropometric characteristics and some functional characteristics of ice-dancers are analysed. It has been shown that the maximum oxygen uptake is similar to that of classical ballet dancers. Tests effected on the ice revealed a high production of lactate, the involvement of the anaerobic metabolism, and high heart rates. It is concluded that the high production of lactate during the free dance on ice is due to the isometric muscular contraction, necessary to maintain certain positions.

The maximal strengths of knee extensor (E) and flexor (F) muscles were compared in a group of 6 male subjects aged 24-31 years. Cross-sectional area (CSA) of E and F was evaluated from planimetric measurements of Nuclear Magnetic Resonance (NMR) imaging axial scans, carried out at five levels along the thigh. Maximal CSA for E was found at 2/3 upper femur height and at 1/3 lower femur height for F. Maximum isometric force (MIF) of E was found to be 135% greater than that of F. The maximum CSA of E was found to be 93% larger than CSA of F. The calculated mechanical advantage of the flexors was estimated to be 13.8% higher than that of the knee extensors (0.116 +/- 0.012 and 0.132 +/- 0.005, respectively). However, when MIF of E and F were standardised for their respective CSA, no significant difference was found between their stress: 80.1 +/- 15.5 N.cm-2 for E and 70.5 +/- 7.0 N.cm-2 for F. From the present study, it is concluded that no significant difference exists between the maximum stress of knee extensor and flexor muscles despite large differences in their absolute values of force and CSA and that the NMR imaging technique enables accurate in-vivo determination of the CSA of individual muscles.

Case report.To present the rehabilitative course, decision-making, and clinical milestones that allowed a top-level professional soccer player to return to full competitive activity 90 days after surgery.The patient was a 35-year-old forward player who sustained an isolated complete tear of the left anterior cruciate ligament (ACL) in the midst of the competitive 2001-2002 season. He was in contention for a position on the Italian World Cup Team that was to be played 135 days after his injury, only if he demonstrated that he could return to play at the highest level before the team was selected. The patient underwent an arthroscopically assisted ACL reconstruction with a double-loop semitendinosus-gracilis autograft 4 days after the injury. Eight days after surgery he began rehabilitation at a rate of 2 sessions a day, 5 days a week, plus 1 session every Saturday morning. These sessions were performed in a pool for aquatic exercises, in a gymnasium for flexibility, coordination, and strength exercises, and on a soccer field for recovery of technical and tactical skills, with continuous monitoring of training intensity.The surgical technique and the progressive rehabilitation program allowed the patient to play for 20 minutes in an official First Division soccer game 77 days after surgery and to play a full game 90 days after surgery. Eighteen months postsurgery, the player had participated in 62 First Division matches, scoring 26 times, and had received no further treatment for his knee.This case report suggests that early return to high-level competition after ACL reconstruction is possible in some instances. Some factors that may have favored the early return include optimal physical fitness before surgery, a strong psychological determination, an isolated ACL lesion, a properly placed and tensioned graft, a personalized progression of volume and intensity of exercise loads, and an appropriate density of rehabilitative training consisting of a mix of gymnasium, pool, and field exercises.

Oremek and Sieffert (1) suggested that extensive physical activity increases prostate-specific antigen (PSA) concentrations. They demonstrated the increase after a standardized exercise on a cycloergometer for 15 min at 75–100 W in many healthy men with different ages. We performed PSA measurements during various sport performances to establish if strenuous exercise increases the serum PSA in young men. We measured PSA on 30 men with a mean age of 27 years (range 18–45) participating in ultraendurance performances of different sports. Twelve men participated in the Pine 24-h, an ultraendurance nonstop 24-h speed ice skating competition (February …

Although there are various descriptive reports concerning exercise-induced gastrointestinal distress, the role of gastrointestinal hormones and/or enzymes is not definitively established. In this study we investigated the behaviour of pepsinogens (PCI and PGII) after an endurance race performed at an altitude of 4,300 m by 13 well-trained marathon runners, with the aim to establish their interrelationship with gastrointestinal distress and with the modifications of gastrin and cortisol. The athletes showed a significant rise in gastrin (p < 0.01) and in cortisol (p < 0.01) and a significant decrease in PGI (p < 0.01) and PGII (p

Physical activity could modify platelet count and platelet indices. Previous reports showed modifications after exercise linked to type and duration of sports performances. The shortage of studies in this field stems from the crucial methodological problem of EDTA (ethylenediaminetetraacetic acid)-dependent, mean platelet volume modifications: the published data on platelets count and indices were obtained by using a light-scattering system without standardization of the period elapsed from drawing to measurement. We present a study of platelet indices performed in athletes participating in an "extreme" performance, a race of 30 km in altitude (6,700 m of ascents and descents), using standardized measurement by an aperture-impedance instrument transferred in the field. The platelet count and mean platelet volume significantly increased in athletes, whereas platelet distribution width decreased. The mean initial values were 240.6*10(9)/L for platelet count, 8.79 fL for mean platelet volume, and 15.79% for platelet distribution width. The correspondent mean final values were 288.4*10(9)/L, 9.14 fL, and 15.48%. The modifications of platelet count and indices were always in the physiological reference range. The entity and the rapidity of platelet count and indices modifications suggest that the more probable source of variation is the recruitment of noncirculating pools of mature platelets. Strenuous exercise does not show abnormal changes of platelet parameters.

Human growth hormone (hGH) characteristically increases during physical exercise. In sports medicine, hGH changes have mostly been described in short-term performances under standardized laboratory procedures. We studied hGH and insulin-like growth factor I (IGF-I) under field conditions in 7 runners performing a marathon at 4000 m of altitude, to study the hormonal changes under extreme endurance effort and to evaluate the release of 22 kDa and 20 kDa monomers under these conditions, in comparison with a control group. The blood samples were taken at sea level, after 1 week of acclimatization, immediately after the run, and after a recovery of 24 h from the marathon. hGH was quantified by using a polyclonal method, a 22 kDa specific monoclonal method and a monoclonal method recognizing both 22 kDa and 20 kDa isoforms. A significant increase in hGH was noted using all methods after the marathon, followed by a significant decrease after recovery. Significant differences between athletes and controls were found only for the measurement after the marathon. No statistically reliable decrease of IGF-I was observed in athletes and controls. We obtained more limited hGH rises than previously described in athletes; the importance of lactate levels indicates that the use of physical exercise as a stimulation test for hGH should be closely standardized. The 20 kDa monomer and other hGH molecular forms played a limited role in the hormone increase: in our experience, elevation of hGH in heavy exercise corresponds mostly to the 22 kDa isoform. We suggest that the evaluation of hGH elevation in sports medicine could be accurately performed using specific 22 kDa monoclonal assays.