The aim of this study was to specify the effects of caffeine on maximal anaerobic power (Wmax). A group of 14 subjects ingested caffeine (250 mg) or placebo in random double-blind order. The Wmax was determined using a force-velocity exercise test. In addition, we measured blood lactate concentration for each load at the end of pedalling and after 5 min of recovery. We observed that caffeine increased Wmax [964 (SEM 65.77) W with caffeine vs 903.7 (SEM 52.62) W with placebo; P less than 0.02] and blood lactate concentration both at the end of pedalling [8.36 (SEM 0.95) mmol.l-1 with caffeine vs 7.17 (SEM 0.53) mmol.l-1 with placebo; P less than 0.01] and after 5 min of recovery [10.23 (SEM 0.97) mmol.l-1 with caffeine vs 8.35 (SEM 0.66) mmol.l-1 with placebo; P less than 0.04]. The quotient lactate concentration/power (mmol.l-1.W-1) also increased with caffeine at the end of pedalling [7.6.10(-3) (SEM 3.82.10(-5)) vs 6.85.10(-3) (SEM 3.01.10(-5)); P less than 0.01] and after 5 min of recovery [9.82.10(-3) (SEM 4.28.10(-5)) vs 8.84.10(-3) (SEM 3.58.10(-5)); P less than 0.02]. We concluded that caffeine increased both Wmax and blood lactate concentration.

This paper provides a summary review of the major biological features concerning the essential oil of turpentine, its origin and use in traditional and modern medicine. More precisely, the safety of this volatile fraction to human health, and the medical, biological and environmental effects of the two major compounds of this fraction (α-and β-pinenes) have been discussed. Key words:Spirits of turpentine, α-pinene, β-pinene Received: July 1, 2009. Accepted : September 28, 2009. Address reprint request to B. Mercier, UPRES EA 4183 "Lipides & Signalisation Cellulaire", Faculté des Sciences de la Vie, Université de Bourgogne 6, Boulevard Gabriel, F-21000 Dijon (e-mail: beamercier@laposte.net). ORIGIN OF TURPENTINEThe term "essential oil of turpentine" designates the terpenic oil, obtained by hydrodistillation of the gem pine. It is also named the "spirits of turpentine", "pine tree terpenic", "pine oleoresin", "gum turpentine", "terpenes oil" or "turpentine from Bordeaux". Due to its pleasant fragrance, the terpenic oil is used in the pharmaceutical industry, perfume industry, food additives and other chemical industries (household cleaning products, paintings, varnishes, rubber, insecticides, etc.) [1]. TRADITIONAL MEDICINE AND TURPENTINEThe eminent doctors of antiquity, Hippocrates, Dioscoride or Galien, used the terpenic oil for its properties against lung diseases and biliary lithiasis. In France, Thillenius, Pitcairn, Récamier and Martinet recommended it against the blennorrhoea and cystitis. Chaumeton, Peschiez, Kennedi, Mérat prescribed it against the neuralgias. It was also used in the treatment of rheumatism, sciatica, nephritis, drop, constipation and mercury salivation. Those scientists also recognized that the terpenic oil may be a booster at an average dose and may have a paralyzing activity at high doses. In Germany, (Rowachol and Rowatinex), Slovenia (Uroterp) and Poland (Terpichol and Terpinex), the traditional drugs for renal and hepatic diseases (especially against cholesterol stones in the gall bladder and the bile duct) contain α-and β-pinenes [2]. Modern phytotherapy describes the following properties of the terpenic oil: antiparasitic, analgesic, revulsive, disinfectant (external use); balsamic, active on bronchial secretion and pulmonary and genito-urinary tract infections, haemostatic, dissolving gallstones, diuretic, antispasmodic, antirheumatic, deworming, being an antidote for poisonings caused by phosphorus [3] and improving the ciliary and secretory activity in patients who present chronic obstructive bronchitis (internal use ) [4]. ENVIRONMENTAL IMPACT OF THE VOLATILE TURPENTINE FRACTIONThe most volatile components of turpentine are two terpenes: alpha (α) and beta (β) pinenes. They are the dominant odorous compounds emitted by trees, shrubs, flowers and grasses [25]. In the lower troposphere, and depending on the weather conditions at the top of the trees, these compounds can react with OH° radicals, ozone, NO 3 radical and O 2 . Indeed, the electric field in the canopy at...

We investigated the aerobic and anaerobic contributions to performance during the Wingate test in sprint and middle-distance runners and whether they were related to the peak aerobic and anaerobic performances determined by two commonly used tests: the force-velocity test and an incremental aerobic exercise test. A group of 14 male competitive runners participated: 7 sprinters, aged 20.7 (SEM 1.3) years, competing in 50, 100 and 200-m events and 7 middle-distance runners, aged 20.0 (SEM 1.0) years, competing in 800, 1,000 and 1,500 m-events. The oxygen uptake (VO2) was recorded breath-by-breath during the test (30 s) and during the first 20 s of recovery. Blood samples for venous plasma lactate concentrations were drawn at rest before the start of the test and during the 20-min recovery period. During the Wingate test mean power (W) was determined and three values of mechanical efficiency, one individual and two arbitrary, 16% and 25%, were used to calculate the contributions of work by aerobic (Waer,ind,16%,25%) and anaerobic (Wan,ind,16%,25%) processes. Peak anaerobic power (Wan,peak) was estimated by the force-velocity test and maximal aerobic energy expenditure (Waer,peak) was determined during an incremental aerobic exercise test. During the Wingate test, the middle-distance runners had a significantly greater VO2 than the sprinters (P < 0.001), who had significantly greater venous plasma lactate concentrations (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

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We investigated in rats the effect of 4 wk of hypodynamia on the respiration of mitochondria isolated from four distinct muscles [soleus, extensor digitorum longus, tibial anterior, and gastrocnemius (Gas)] and from subsarcolemmal (SS) and intermyofibrillar (IMF) regions of mixed hindlimb muscles that mainly contained the four cited muscles. With pyruvate plus malate as respiratory substrate, 4 wk of hindlimb suspension produced an 18% decrease in state 3 respiration for IMF mitochondria compared with those in the control group (P < 0.05). The SS mitochondria state 3 were not significantly changed. Concerning the four single muscles, the mitochondrial respiration was significantly decreased in the Gas muscle, which showed a 59% decrease in state 3 with pyruvate + malate (P < 0.05). The other muscles presented no significant decrease in respiratory rate in comparison with the control group. With succinate + rotenone, there was no significant difference in the respiratory rate compared with the respective control group, whatever the mitochondrial origin (SS, or IMF, or from single muscle). We conclude that 4 wk of hindlimb suspension alters the respiration of IMF mitochondria in hindlimb skeletal muscles and seems to act negatively on complex I of the electron-transport chain or prior sites. The muscle mitochondria most affected are those isolated from the Gas muscle.

We investigated the effects of passive and partially active recovery on lactate removal after exhausting cycle ergometer exercise in endurance and sprint athletes. A group of 14 men, 7 endurance-trained (ET) and 7 sprint-trained (ST), performed two maximal incremental exercise tests followed by either passive recovery (20 min seated on cycle ergometer followed by 40 min more of seated rest) or partially active recovery [20 min of pedalling at 40% maximal oxygen uptake (VO2max) followed by 40 min of seated rest]. Venous blood samples were drawn at 5 min and 1 min prior to exercise, at the end of exercise, and during recovery at 1, 2, 3, 4, 5, 6, 8, 10, 15, 20, 30, 40, 50, 60 min post-exercise. The time course of changes in lactate concentration during the recovery phases were fitted by a bi-exponential time function to assess the velocity constant of the slowly decreasing component (tau 2) expressing the rate of blood lactate removal. The results showed that at the end of maximal exercise and during the 1st min of recovery, ET showed higher blood lactate concentrations than ST. Furthermore, ET reached significantly higher maximal exercise intensities [5.1 (SEM 0.5) W.kg-1 vs 4.0 (SEM 0.3) W.kg-1, P < 0.05] and VO2max [68.4 (SEM 1.1) ml.kg-1.min-1 vs 55.5 (SEM 5.1) ml.kg-1.min-1, P < 0.01]. There was no significant difference between the two groups during passive recovery for tau 2. During partially active recovery, tau 2 was higher than during passive recovery for both groups (P < 0.001), but ET recovered faster and sooner than ST (P < 0.05). Compared to passive recovery, the tau 2 measured during partially active recovery was increased threefold in ET and only 1.5-fold in ST. We concluded that partially active recovery potentiates the enhanced ability to remove blood lactate induced by endurance training.

The purpose of this study was to determine the effects of age in relation to anthropometric characteristics upon maximal anaerobic power of legs in sixty-nine young boys aged 11 to 19 years. Maximal anaerobic power (Wmax) was measured by the force-velocity test. Lean body mass (LBM) was determined from all four skin-fold thickness measurements, leg volume (LV) was estimated by anthropometric method, and anthropometric measurements were used to determine total muscular mass (TMM). Wmax increased significantly (F = 44.1, p less than 0.001) between 11 and 19 years and was correlated with LV (r = 0.84) and TMM (r = 0.88). It was most highly correlated with LBM (r = 0.94), which best explained the percentage of the total variance of Wmax (88%). Normalized Wmax (Wmax/LBM) also increased significantly between 11 and 19 years (F = 21.9, p less than 0.001). In conclusion, Wmax determined by the force-velocity test was closely related to anthropometric characteristics, especially LBM, during the growth period. Furthermore, even when corrected for lean body mass, maximal anaerobic power was always found to increase. This suggests that other undetermined factors, in addition to the amount of lean tissue mass, may explain the increase of Wmax during the force-velocity test.

The aim of the present study was to assess blood lactate concentrations ([LA], mmol x L(-1)) and oxygen uptake (VO2, L x min(-1), mL x kg(-1) x min(-1)) during incremental exercise in subjects with sickle cell trait (SCT) only, i.e., sedentary subjects with SCT without anemia and/or associated alpha thalassemia. Anemia was ruled out using hemoglobin (Hb) level, and alphathalassemia was ruled out using hemoglobin S (HbS) percentage and concomitant Hb level and mean corpuscular volume (MCV). Comparison was made with control subjects with normal Hb, matched for physical fitness, anthropometric data, and hematological parameters. All subjects underwent an incremental exercise test (IET) using an electromagnetic cycle ergometer. Ventilatory data, i.e., minute ventilation (VE, L x min(-1)), oxygen uptake (VO2, mL x min(-1), mL x Kg(-1) x min(-1)) carbon dioxide production (VO2, mL x min(-1)), ventilatory equivalent for O2(VE x VO2(-1))and for CO2 (VE x VO2(-1)), and respiratory exchange ratio (RER, VO2 x VO2(-1)), were collected every minute during IET and the recovery period using a breath-by-breath automated system. Heart rate (HR, beats x min(-1)) was measured every minute using an EKG. Blood sampling was done every minute during IET and the first 5 min of the recovery period, and then every 5 min until the 20th minute of recovery. [LA] were determined by an enzymatic method with a spectrophotometer. Comparisons of all mean cardioventilatory variables showed no significant differences in subjects with SCT versus controls during IET and recovery. In contrast, analysis of variance revealed significantly lower time courses of [LA] during IET (P < 0.05) and recovery (P < 0.05), whereas time courses of VO2 were similar (P > 0.05). We conclude that the lower [LA] exhibited by subjects with SCT during incremental exercise and the subsequent recovery was not associated with concomitant oxygen uptake impairment.