Intense Exercise

Top PDF Intense Exercise:

Sprint Training Reduces Urinary Purine Loss Following Intense Exercise in Humans

Sprint Training Reduces Urinary Purine Loss Following Intense Exercise in Humans

The ATP content of untrained human skeletal muscle is about 20-25 mmol.kg -1 dry mass (d.m.), and several reports have demonstrated that intense intermittent sprint training can lower the resting content by up to 20% (Hellsten-Westing et al. 1993a; Stathis et al. 1994; Hellsten et al. 2004). The factors responsible for the set point of resting muscle adenine nucleotide (AdN=ATP+ADP+AMP) content are unknown, however, it is influenced by the balance between loss of purine base from the muscle and its production via de novo purine synthesis. Intense exercise results in a transient reduction of ATP and concomitant accumulation of IMP (Stathis et al. 1994). Most of this IMP is rapidly resynthesised to ATP during recovery, although a small portion is further degraded and results in the production of the purine bases inosine and hypoxanthine (Hx; Stathis et al. 1994). Purine bases, not recovered intramuscularly via purine salvage, efflux the muscle (Hellsten et al. 1999) and accumulate in the plasma (Bangsbo et al. 1992; Tullson et al. 1995; Stathis et al. 1999). Once in the plasma purine bases are not recovered by skeletal muscle (Hellsten et al. 1999). The magnitude of purine loss can be between 5% and 9% of the resting muscle ATP content (Bangsbo et al. 1992; Hellsten et al. 1999). It has been reported that the plasma purines are excreted in the urine (Nasrallah and Al Khalidi 1964; Sutton et al. 1980; Stathis et al. 1999), or converted to uric acid (Hellsten et al. 1994) and subsequently excreted (Nasrallah and Al Khalidi 1964; Sorensen and Levinson 1975; Stathis et al. 1999). Sorensen and Levison (1975) demonstrated that, in a resting individual, the uric acid loss via the gut is one third, whilst via the urine is two thirds of the total uric acid loss in the untrained individual.

22 Read more

The Effect of Acute Intense Exercise on Activity of Antioxidant Enzymes in Smokers and Non-smokers

The Effect of Acute Intense Exercise on Activity of Antioxidant Enzymes in Smokers and Non-smokers

Abstract: Acute intense exercise causes significant oxidative stress and consequently an increase in total antioxidant capacity; however, the mechanisms and combined effects of intense exercise and smoking on oxidative stress among active and non-active smokers are not clear. The aim of this study was to investigate the effect of acute intense exercise on antioxidant enzyme activity responses in active and non-active individuals exposed to cigarette smoke. The study included 40 subjects who were equally classified as: smokers that did exercise (SE), smokers that did not do exercise (SnE), non- smokers that did exercise (NSE), and non-smokers that did not do exercise (NSnE). The adjusted Astrand test was used to exhaust the subjects. Salivary enzymes of peroxidase (POX), catalase (CAT), and superoxide dismutase (SOD) were measured, by spectrophotometry methods, at 3 different time points: pre-test (TP1), post-test (TP2), and one hour after finishing the test (TP3). Significant (p<0.05) group x time interactions were found for the three enzymes. Salivary POX, CAT and SOD increased in all groups from TP1 to TP2 and decreased from TP2 to TP3. Only the NSE showed a significant difference between TP1 to TP3 in POX and SOD by +0.011 ± 0.007 and +0.075 ± 0.02 (U/ml), respectively. The NSE showed significantly higher levels of POX, CAT and SOD in TP2 compared to the other groups. Furthermore, NSE and NSnE had higher levels of POX, CAT and SOD in TP1 and TP3 (p<0.05) compared with SE and SnE. Only in the NSnE, were no differences observed in CAT compared with SE and SnE in TP3. These results showed that the antioxidant level at rest and in the recovery time after the acute intense exercise was lower in SE and SnE compared with NSE and NSnE, suggesting that smoking habit may reduce the ameliorating effect of regular physical activity on acute exercise-induced oxidative stress.

12 Read more

Lycopene Supplementation Attenuates Oxidative Stress Parameters in the Plasma of Humans with Cad after Intense Exercise

Lycopene Supplementation Attenuates Oxidative Stress Parameters in the Plasma of Humans with Cad after Intense Exercise

To investigate the effects of moderate and intense exercise (ME,IE) and lycopene (L) supplementation on oxidative stress biomarkers in patients with CAD. Rehabilitation clinic.Thirty-two male volunteers with CAD (55.65  2.27 years, 77.27  3.95 kg, 171.9  2.80 cm) were divided into four groups; ME-Placebo (n = 7), ME + L (n = 8), IE-Placebo (n = 8) and IE-L (n = 9). Blood samples (12 mL) were collected before supplementation (one cereal bars – 15 mg of syn- thetic lycopene) and exercise (45 min plus 15 min of stretching, 3/wk) and after five weeks of supplementation and 72 h after exercise. Nitrite/nitrate concentrations (NOx), lipoperoxidation (TBARS levels), protein carbonylation (PC) and superoxide dismutase (SOD) and catalase (CAT) activity were assessed in plasma. NOx decreased significantly in the ME-P, IE-P and ME-L groups at 72 h after exercise and increased in the IE-L 72 h after the last exercise session. The IE-L group demonstrated decreased TBARS at 72 h after the last exercise session. The level of PC increased only in EI-P at 72 h after the last exercise session, while only the EI-L group presented a reduction. SOD increased signifi- cantly in both placebo groups 72 h after the last exercise session and decreased in the ME-L group 72 h after in rela- tion to placebo groups. CAT increased in ME-P, IE-P and IE-L groups only at 72 h after the last exercise session. The lycopene supplementation attenuates some markers of oxidative stress associated with IE Lycopene also had dissimilar effects on some markers of oxidative stress in subjects undertaking ME versus IE.

8 Read more

Case Study: The Prevention of Diabetes Through Diet and Intense Exercise

Case Study: The Prevention of Diabetes Through Diet and Intense Exercise

treadmill 40 minutes/day, six days per week. After nutritional assessment and intervention, L.H. followed an 1,800 kcal/day meal plan. Food items such as flaxseeds, wheat germ, pecans, cinna- mon powder, and skim milk were included with the morning cereal. Lunch remained the same as before. Dinner, now scheduled at 6:00 p.m., consisted mostly of baked fish fillet or salmon, steamed rice, and vegetables. A bedtime snack included low-fat milk and a granola bar. The intense exercise program and diet was composed of an average caloric deficit of 1,000 kcal/day (500 kcal from food intake and 500 kcal burned on the treadmill). 2. What were the outcomes of the treatment after 2 months?

5 Read more

The Impact of Fallow-Up Thyroid Hormone Alterations and Its Stimulant after Moderate and Intense Exercise in Male Athletes

The Impact of Fallow-Up Thyroid Hormone Alterations and Its Stimulant after Moderate and Intense Exercise in Male Athletes

an increase in fT3 levels with no significant change in TSH, T4, fT4 and reverse T3 (rT3) (9). Another study done by Deligiannis et. al. looking at the thyroid hormone response to swimming for 30 minutes at varying water temperatures showed that TSH and fT4 levels were significantly increased at 20°C as compared to 32°C but no significant effect was seen on T3 (10). Pakerinen et. al. study on the effects of one week of very intense strength training on the thyroid hormones of male weight lifters showed a significant decrease in TSH, T3 and T4 with unchanged fT4, rT3 and thyroid binding globulin (TBG) (11, 12).

6 Read more

Intense exercise increases HDL level in children regardless of body weight

Intense exercise increases HDL level in children regardless of body weight

level change; in general, it has been reported that changes in HDL concentration requires at least 10-week period program. From one to two days after a single ex- ercise session, adults present an elevation in HDL levels while the full effect is an increase in HDL2-c and a de- crease in HDL3-c. Therefore, both a single session and an exercise program have independent effects on lipid profile and lipoprotein level in adults. On the other hand, children use a higher proportion of lipids while exercis- ing than adults [21].

5 Read more

Effect of Intense Exercise on Inflammatory Cytokines and Growth Mediators in Adolescent Boys

Effect of Intense Exercise on Inflammatory Cytokines and Growth Mediators in Adolescent Boys

We hypothesized that acute alterations in the cir- culating levels of the GH3 IGF-I axis and in the proinflammatory cytokines would be substantially catabolic in response to single bouts of intense exer- cise in adolescents. We further hypothesized that factors such as increasing fitness would attenuate the catabolic response, suggesting an ability of growing children to adapt hormonally to repeated exercise bouts (ie, training). To test these hypotheses, we studied the effect of a single, typical, high school wrestling practice session. Wrestling was chosen spe- cifically because individual practice sessions are in- tense and because high school wrestlers are known to develop GH resistance during the course of a standard 3- to 4-month season. 15

11 Read more

Case Study: Diabetes in a Patient With Cirrhosis

Case Study: Diabetes in a Patient With Cirrhosis

treadmill 40 minutes/day, six days per week. After nutritional assessment and intervention, L.H. followed an 1,800 kcal/day meal plan. Food items such as flaxseeds, wheat germ, pecans, cinna- mon powder, and skim milk were included with the morning cereal. Lunch remained the same as before. Dinner, now scheduled at 6:00 p.m., consisted mostly of baked fish fillet or salmon, steamed rice, and vegetables. A bedtime snack included low-fat milk and a granola bar. The intense exercise program and diet was composed of an average caloric deficit of 1,000 kcal/day (500 kcal from food intake and 500 kcal burned on the treadmill). 2. What were the outcomes of the treatment after 2 months?

5 Read more

Exercise-induced stress behavior, gut-microbiota-brain axis and diet: a systematic review for athletes

Exercise-induced stress behavior, gut-microbiota-brain axis and diet: a systematic review for athletes

Other neuromodulators that may influence fatigue and mood during exercise include pro-inflammatory cyto- kines and ammonia. Increases in pro-inflammatory cyto- kines like IFNγ and IL6 have been associated with reduced exercise tolerance, acute viral or bacterial infec- tion and increased tryptophan catabolism which could thus limit brain serotonin synthesis [100], leading to de- pressive behavior. Accumulation of ammonia in the blood and brain during exercise could also negatively affect the CNS function causing fatigue. Guezennec et al [101] investigated if exhaustive exercise increased am- monia detoxification in the brain mediated by glutamine synthesis which, subsequently would influence glutamate and GABA levels. They discovered that both trained and untrained rats that ran until exhausted presented an in- crease in serum ammonia, which can reduce brain en- ergy by stimulating the Krebs cycle and glycolysis. The trained exercise group had levels of ammonia 50% higher than the untrained group and also presented lower levels of the excitatory neurotransmitter glutamate as well as a decrease in GABA in the striatum of the brain [101]. These findings show that exercise stimulates glutamine synthesis that’s used for ammonia detoxifica- tion resulting in decreased production of the excitatory neurotransmitter glutamate possibly causing fatigue in endurance athletes [101]. Glutamine, a nonessential amino acid that’s the most abundant in the human body [102], is crucial not only for the glutamate and GABA synthesis but also for optimal functioning of leukocytes such as lymphocytes and macrophages, T cell prolifera- tion and function [104], intestinal enterocytes growth [102]. Therefore, prolonged intense exercise could nega- tively affect neurotransmitter homeostasis and immune response when glutamine levels are depleted [80, 81] in order to detoxify ammonia in the brain causing a more excitatory-glutamate driven response to exercise- induced stress and a decline in GABA-mediated inhibi- tory pathways. Additionally, depleted serum glutamine levels mean less uptake in the intestines leaving the enterocytes more susceptible to intestinal permeability [105].

21 Read more

Maximal Oxygen Levels as an Incremental Exercise to Optimise Individual Training Prescription with the Aim of Rectifying Weaknesses of Elite Algerian Soccer

Maximal Oxygen Levels as an Incremental Exercise to Optimise Individual Training Prescription with the Aim of Rectifying Weaknesses of Elite Algerian Soccer

The present study compared the improvements of soccer players under 18 years from Algerian elite S-League players using the yo-yo intermittent test. Allowed by Yo-Yo IR level 1 (Yo-Yo IR1) as a simple and valid way to obtain important information of an individual's capacity to perform repeated intense exercise and to examine changes in performance [36] associated with body composition (BMI & BFP), weight loss goals [4,10] and athletes’ aerobic fitness programs [20,28,29,31,37].

7 Read more

Case Study: Uncontrolled Type 2 Diabetes in a 48-Year-Old Woman on Interferon β-1b Treatment for Multiple Sclerosis

Case Study: Uncontrolled Type 2 Diabetes in a 48-Year-Old Woman on Interferon β-1b Treatment for Multiple Sclerosis

treadmill 40 minutes/day, six days per week. After nutritional assessment and intervention, L.H. followed an 1,800 kcal/day meal plan. Food items such as flaxseeds, wheat germ, pecans, cinna- mon powder, and skim milk were included with the morning cereal. Lunch remained the same as before. Dinner, now scheduled at 6:00 p.m., consisted mostly of baked fish fillet or salmon, steamed rice, and vegetables. A bedtime snack included low-fat milk and a granola bar. The intense exercise program and diet was composed of an average caloric deficit of 1,000 kcal/day (500 kcal from food intake and 500 kcal burned on the treadmill). 2. What were the outcomes of the treatment after 2 months?

5 Read more

Effects of ingesting protein with various forms of carbohydrate following resistance-exercise on substrate availability and markers of anabolism, catabolism, and immunity

Effects of ingesting protein with various forms of carbohydrate following resistance-exercise on substrate availability and markers of anabolism, catabolism, and immunity

Ingestion of CHO and PRO following intense exercise has been reported to increase insulin levels, optimize glyco- gen resynthesis, enhance PRO synthesis, and lessen the immuno-suppressive effects of intense exercise [2,3,8,14,16,35]. Since different forms of CHO have vary- ing glycemic effects [28,29,34], the purpose of this study was to determine whether the type of CHO ingested with PRO following resistance-exercise affects blood glucose availability, insulin levels, markers of anabolism and catabolism, and/or general immune markers during the first two hours of recovery. The major findings of this study were: 1.) ingesting CHO with PRO following resist- ance-training promoted significant increases in insulin levels; 2.) no significant differences were observed among the forms of CHO ingested on insulin levels suggesting that each of these types of CHO can be an effective source of CHO for post-exercise CHO/PRO supplements; 3.) that glucose levels were maintained to a greater degree in sub- jects ingesting honey as the source of CHO; and, 4.) post- exercise nutritional supplementation did not significantly affect the time course of testosterone, cortisol, the ratio of testosterone to cortisol, muscle and liver enzyme efflux, or general markers of immunity during the first two hours of recovery following resistance-exercise. These findings add to a growing body of literature indicating that ingestion of CHO and PRO following exercise can stimulate insulin levels and thereby anabolic processes [3,5,12,18,20,27]. Moreover, they extend our understanding of how differ- ent sources of CHO with differing glycemic responses influence glucose availability, insulin levels, and recovery indices. The following provides additional insight into the results observed.

11 Read more

Ergogenic effects of caffeine and sodium bicarbonate supplementation on intermittent exercise performance preceded by intense arm cranking exercise

Ergogenic effects of caffeine and sodium bicarbonate supplementation on intermittent exercise performance preceded by intense arm cranking exercise

In the present study caffeine increased Yo-Yo IR2 per- formance by 14% compared to the placebo-trial, which is in line with other findings [3,4]. Caffeine has multiple physiological effects that may promote fatigue resistance during intense exercise, such as elevating the catechol- amine levels [24] and reducing muscle interstitial K + ac- cumulation [5]. Peak blood glucose concentrations were higher in the caffeine-trial than placebo, which is in ac- cordance with findings by others [5], indicating an ele- vated catecholamine response, which may facilitate the Na + -K + ATPase activity [25]. The arm protocol has been shown to increase the accumulation of interstitial potas- sium during leg exercise [15], and caffeine may reduce this effect by increasing the pump activity in the Na + -K + APTase directly or via an elevated catecholamine response [5,25]. Finally caffeine may have an effect on central mechanisms associated with fatigue [23,26], how- ever, the RPE rating were not different between the caf- feine and placebo trials in the present study. Caffeine is well-known to affect the central nervous system re- sponse mediated via antagonism of adenosine receptors, which dampens pain perception and attenuates fatigue [27]. However, during high-intensity intermittent exer- cise caffeine-induced effects on RPE appear to be ne- gated [6], which is supported by this study.

8 Read more

Download (429kB)

Download (429kB)

likely explained by several other factors. A lesser K + release from contracting muscles would be anticipated due to the lesser contraction time with short sprint durations, with less time for K + overflow from the muscle interstitium into the venous circulation before rapid K + re-accumulation into the muscle cells during recovery. This K + release might also have been attenuated by already increased muscle NKA activation due to the preceding exercise bouts, as muscle NKA is highly activated by even brief intense contractions (McKenna et al. 2003). The recovery periods with intermittent exercise, with 20 s recovery between sprints within each set and 2.5 min recovery between sets, would also each have facilitated subsequent muscle cellular K + reuptake. These effects might be partially offset by a smaller endogenous catecholamine response anticipated during intermittent compared to continuous exercise. The low [K + ] a and [K

24 Read more

The Effect of Exercise on Paraoxonase-1 Activity and Lipid Profile in Obesity and Insulin Resistance Conditions

The Effect of Exercise on Paraoxonase-1 Activity and Lipid Profile in Obesity and Insulin Resistance Conditions

In the absence of insulin, regular physical activity facilitates the glucose entry into the cell via affecting several signaling pathways. Moreover, regular exercise improves the lipid profile and increases the paraoxonase-1 (PON-1) activity. PON-1 interacts with High- density lipoprotein (HDL) and, in the presence of calcium, hydrolyzes free radicals, prevents low-density lipoprotein (LDL) oxidation, maintains homocysteine structure in the blood, and inhibits hemoglobin glycation. These factors explain one of the beneficial effects of regular exercise on prevention of cardiovascular diseases. In addition, there is a positive relationship between decreased PON-1 activity and the occurrence of cardiovascular diseases, renal failure, gastric cancer, dyslipidemia, insulin resistance, and even Alzheimer’s disease. Therefore, this study was conducted to evaluate the effect of physical activity on the PON-1 activity and lipid profile. Regular physical activity increased HDL and PON-1 activity in patients with metabolic syndrome. Since PON-1 binds to HDL and increased HDL probably increases the PON-1 activity as well. This finding suggests that regular exercise decreases the effect of one bout exercise on PON-1 response. In addition, in order to improve metabolic syndromes, it is advised to perform aerobic exercise for 150 minutes per week with an intensity of 40-60% of the heart rate reserve (HRR). The exercises should be preferably performed in 3-5 sessions per week according to the intensity. Based on the disease progression, type of consumed drugs, and certain considerations in each group of patients, aerobic, resistance, and flexibility exercises can be performed by using large muscle groups in a continuous training mode. However, in dyslipidemia, continuous aerobic exercises are preferred.

12 Read more

Follow-Up Alterations of Catecholamine Hormones after an Intensive Physical Activity

Follow-Up Alterations of Catecholamine Hormones after an Intensive Physical Activity

All in all, the results are not compatible with Steinberg et al. (2000) and Jacob et al. (2004). In these studies, the level of adrenalin and noradrenalin after cycling exercise had changed. The results are also different form Zouhal (1998). This can be attributed to intensity of exercise. In Zouhal study, Wingate test was used as an anaerobic exercise.

5 Read more

The impact of brief high-intensity exercise on blood glucose levels

The impact of brief high-intensity exercise on blood glucose levels

Results: Six studies of nondiabetics (51 males, 14 females) requiring 7.5 to 20 minutes/week of HIE are reviewed. Two weeks of sprint interval training increased insulin sensitivity up to 3 days postintervention. Twelve weeks near maximal interval running (total exercise time 40 minutes/week) improved BG to a similar extent as running at 65% VO 2max for 150 minutes/ week. Eight studies of diabetics (41 type 1 and 22 type 2 subjects) were reviewed. Six were of a single exercise session with 44 seconds to 13 minutes of HIE, and the others were 2 and 7 weeks duration with 20 and 2 minutes/week HIE, respectively. With type 1 and 2 diabetes, BG was generally higher during and up to 2 hours after HIE compared to controls. With type 1 diabetics, BG decreased from midnight to 6 AM following HIE the previous morning. With type 2 diabetes, a single session improved postprandial BG for 24 hours, while a 2-week program reduced the average BG by 13% at 48 to 72 hours after exercise and also increased GLUT4 by 369%.

10 Read more

A six week modified sprint interval training program incorporating extended exercise bouts does not increase maximal cardiac output

A six week modified sprint interval training program incorporating extended exercise bouts does not increase maximal cardiac output

Dempsey, Chosy, Shahidi, & Reddan, 1974). Increases in production of red blood cells and haemoglobin are induced by the hormone erythropoietin (whether endogenous or exogenous) (Silverthorn, 2004). Increases in haemoglobin, irrespective of changes in blood volume, improve exercise performance and oxygen uptake (Kanstrup & Ekblom, 1984). A molecule similar to haemoglobin, myoglobin, is found in muscle tissue. Oxygen binds to myoglobin (oxymyoglobin) facilitating oxygen transport to the mitochondria (myoglobin also acts as an oxygen store) (Wilmore & Costill, 2004b). Theoretically, an increase in myoglobin could improve V O 2max but studies have produced equivocal

61 Read more

The Effect of an Intense Anaerobic Exercise Session on Serum Levels of IgG, IgM and IgA in Handball, Volleyball and Climbing Sports

The Effect of an Intense Anaerobic Exercise Session on Serum Levels of IgG, IgM and IgA in Handball, Volleyball and Climbing Sports

amounts of IgA, IgG, IgG2 and IgG3 were significantly increased [12]. However, some other studies have pointed out a reduction in the concentration of immunoglobulin. David et al. (2007), for example, reported that the levels of serum IgG and IgM of ten elite male runners who had intensive training for three weeks had a significant decrease (average 38%) [13]. Demytro et al. (2002), Daly and his colleague (1998), Gleason et al. (1999) and Gleason and Mcdonald (1995) all reported decreased secretion of IgA [14, 15, 16, 17]. On the other hand, many studies have reported no change in immunoglobulin concentrations. For example, Crdova et al. (2010) reported that a volleyball tournament season has no effect on serum immunoglobulin IgA [18]. Mashiko and colleagues (2004) showed that after 20 days of intense training of rugby, significant changes were observed in serum levels of IgG and IgM in male athletes, while several other studies have reported no change in IgA concentration [19]. Several studies have also indicated changes in the amount of immunoglobulin secretion in marathon runners [20, 21, 22], ultramarathon [23] and swimming [24].

8 Read more

Sodium bicarbonate ingestion improves Yo-Yo intermittent recovery test 1 performance: a randomized crossover trial

Sodium bicarbonate ingestion improves Yo-Yo intermittent recovery test 1 performance: a randomized crossover trial

size of N = 6 would be adequate to obtain statistical power of 0.8 for a two-tailed test. Therefore, to allow for dropouts, eight recreationally active males (age: 26 ± 4 yr, body height: 178 ± 6 cm, body mass: 82 ± 10 kg) volunteered to participate in the study. Participants had abstained from exercise and alcohol for the previous 24 h.

6 Read more

Show all 7765 documents...