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Journal of The International Society of Sports Nutrition | 2010

Effects of alfa-hydroxy-isocaproic acid on body composition, DOMS and performance in athletes

Antti Mero; Tuomo Ojala; Juha J. Hulmi; Risto Puurtinen; Tuomo Karila; Timo T. Seppälä

BackgroundAlfa-Hydroxy-isocaproic acid (HICA) is an end product of leucine metabolism in human tissues such as muscle and connective tissue. According to the clinical and experimental studies, HICA can be considered as an anti-catabolic substance. The present study investigated the effects of HICA supplementation on body composition, delayed onset of muscle soreness (DOMS) and physical performance of athletes during a training period.MethodsFifteen healthy male soccer players (age 22.1+/-3.9 yr) volunteered for the 4-week double-blind study during an intensive training period. The subjects in the group HICA (n = 8) received 583 mg of sodium salt of HICA (corresponding 500 mg of HICA) mixed with liquid three times a day for 4 weeks, and those in the group PLACEBO (n = 7) received 650 mg of maltodextrin mixed with liquid three times a day for the same period. According to a weekly training schedule, they practiced soccer 3 - 4 times a week, had strength training 1 - 2 times a week, and had one soccer game during the study. The subjects were required to keep diaries on training, nutrition, and symptoms of DOMS. Body composition was evaluated with a dual-energy X-ray absorptiometry (DXA) before and after the 4-week period. Muscle strength and running velocity were measured with field tests.ResultsAs compared to placebo, the HICA supplementation increased significantly body weight (p < 0.005) and whole lean body mass (p < 0.05) while fat mass remained constant. The lean body mass of lower extremities increased by 400 g in HICA but decreased by 150 g in PLACEBO during the study. This difference between the groups was significant (p < 0.01). The HICA supplementation decreased the whole body DOMS symptoms in the 4th week of the treatment (p < 0.05) when compared to placebo. Muscle strength and running velocity did not differ between the groups.ConclusionAlready a 4-week HICA supplementation of 1.5 g a day leads to small increases in muscle mass during an intensive training period in soccer athletes.


European Journal of Clinical Nutrition | 2015

Effect of diet composition on acid-base balance in adolescents, young adults and elderly at rest and during exercise.

E-M Hietavala; Jeffrey R. Stout; Juha J. Hulmi; Harri Suominen; Hannu Pitkänen; Risto Puurtinen; Harri Selänne; Heikki Kainulainen; Antti Mero

Background:Diets rich in animal protein and cereal grains and deficient in vegetables and fruits may cause low-grade metabolic acidosis, which may impact exercise and health. We hypothesized that (1) a normal-protein diet with high amount of vegetables and fruits (HV) induces more alkaline acid–base balance compared with a high-protein diet with no vegetables and fruits (HP) and (2) diet composition has a greater impact on acid–base balance in the elderly (ELD).Subjects/methods:In all, 12–15 (adolescents (ADO)), 25–35 (young adults (YAD)) and 60–75 (ELD)-year-old male and female subjects (n=88) followed a 7-day HV and a 7-day HP in a randomized order and at the end performed incremental cycle ergometer tests. We investigated the effect of diet composition and age on capillary (c-pH) and urine pH (u-pH), strong ion difference (SID), partial pressure of carbon dioxide (pCO2) and total concentration of weak acids (Atot). Linear regression analysis was used to examine the contribution of SID, pCO2 and Atot to c-pH.Results:In YAD and ELD, c-pH (P⩽0.038) and u-pH (P<0.001) were higher at rest after HV compared with HP. During cycling, c-pH was higher (P⩽0.034) after HV compared with HP at submaximal workloads in YAD and at 75% of VO2max (maximal oxygen consumption) in ELD. The contribution of SID, pCO2 and Atot to c-pH varied widely. Gender effects or changes in acid–base balance of ADO were not detected.Conclusions:A high intake of vegetables and fruits increases blood and u-pH in YAD and ELD. ELD compared with younger persons may be more sensitive for the diet-induced acid–base changes.


Journal of The International Society of Sports Nutrition | 2010

Moderate energy restriction with high protein diet results in healthier outcome in women

Antti Mero; Heikki Huovinen; Olle Matintupa; Juha J. Hulmi; Risto Puurtinen; Hannele Hohtari; Tuomo Karila

BackgroundThe present study compares two different weight reduction regimens both with a moderately high protein intake on body composition, serum hormone concentration and strength performance in non-competitive female athletes.MethodsFifteen normal weighted women involved in recreational resistance training and aerobic training were recruited for the study (age 28.5 ± 6.3 yr, height 167.0 ± 7.0 cm, body mass 66.3 ± 4.2 kg, body mass index 23.8 ± 1.8, mean ± SD). They were randomized into two groups. The 1 KG group (n = 8; energy deficit 1100 kcal/day) was supervised to reduce body weight by 1 kg per week and the 0.5 KG group (n = 7; energy deficit 550 kcal/day) by 0.5 kg per week, respectively. In both groups protein intake was kept at least 1.4 g/kg body weight/day and the weight reduction lasted four weeks. At the beginning of the study the energy need was calculated using food and training diaries. The same measurements were done before and after the 4-week weight reduction period including total body composition (DXA), serum hormone concentrations, jumping ability and strength measurementsResultsDuring the 4-week weight reduction period there were no changes in lean body mass and bone mass, but total body mass, fat mass and fat percentage decreased significantly in both groups. The changes were greater in the 1 KG group than in the 0.5 KG group in total body mass (p < 0.001), fat mass (p < 0.001) and fat percentage (p < 0.01). Serum testosterone concentration decreased significantly from 1.8 ± 1.0 to 1.4 ± 0.9 nmol/l (p < 0.01) in 1 KG and the change was greater in 1 KG (30%, p < 0.001) than in 0.5 KG (3%). On the other hand, SHBG increased significantly in 1 KG from 63.4 ± 17.7 to 82.4 ± 33.0 nmol/l (p < 0.05) during the weight reducing regimen. After the 4-week period there were no changes in strength performance in 0.5 KG group, however in 1 KG maximal strength in bench press decreased (p < 0.05) while endurance strength in squat and counter movement jump improved (p < 0.05)ConclusionIt is concluded that a weight reduction by 0.5 kg per week with ~1.4 g protein/kg body weight/day can be recommended to normal weighted, physically active women instead of a larger (e.g. 1 kg per week) weight reduction because the latter may lead to a catabolic state. Vertical jumping performance is improved when fat mass and body weight decrease. Thus a moderate weight reduction prior to a major event could be considered beneficial for normal built athletes in jumping events.


Journal of Strength and Conditioning Research | 2014

Effects of carbohydrate ingestion on acute leukocyte, cortisol, and interleukin-6 response in high-intensity long-distance running.

Johanna K. Ihalainen; Timo Vuorimaa; Risto Puurtinen; Ismo Hämäläinen; Antti Mero

Abstract Ihalainen, JK, Vuorimaa, T, Puurtinen, R, Hämäläinen, I and Mero, AA. Effects of carbohydrate ingestion on acute leukocyte, cortisol, and interleukin-6 response in high-intensity long-distance running. J Strength Cond Res 28(10): 2786–2792, 2014—The purpose of this study was to investigate the effect of ingestion of fluids with different carbohydrate concentrations (0, 1.5, and 7%) on the acute immune stress responses after high-intensity long-distance running. Continuous 18- to 20-km run was performed at 75% of maximal oxygen uptake with carbohydrate supplementation (CHO7%, 7% carbohydrate solution) and low-carbohydrate supplementation (lowCHO1.5%, 1.5% carbohydrate solution) in a randomized, double-blind, placebo (PLA) controlled design. Seven recreational runners (4 men and 3 women) completed all 3 trials. Blood was collected at baseline (PRE) and immediately after the run (POST). The running task induced significant (p ⩽ 0.05) increases in leukocyte (white blood cells), neutrophil, and interleukin-6 (IL-6) counts in every trial. There was a significant (p ⩽ 0.05) increase in cortisol with PLA and lowCHO1.5% but not with CHO7%. Increase in total leukocyte and neutrophil concentration was significantly lower with CHO7% compared with PLA (p ⩽ 0.05). Postexercise IL-6 levels were significantly elevated when compared with baseline in all conditions (p ⩽ 0.05). Interleukin-6 (IL-6) concentrations did not differ significantly between trials. LowCHO1.5% sport drink did not significantly differ from PLA in measured variables, which indicated that the amount and rate of carbohydrate ingestion (15 g, 10 g·h−1) in low-carbohydrate sport drink was not enough to significantly protect from the stress induced by high-intensity long-distance running, whereas the ingestion of CHO7% (45 g·h−1) blunted the significant cortisol response and significantly decreased the leukocyte response.


Journal of The International Society of Sports Nutrition | 2012

Low-protein vegetarian diet does not have a short-term effect on blood acid–base status but raises oxygen consumption during submaximal cycling

Enni-Maria Hietavala; Risto Puurtinen; Heikki Kainulainen; Antti Mero

BackgroundAcid–base balance refers to the equilibrium between acids and bases in the human body. Nutrition may affect acid–base balance and further physical performance. With the help of PRAL (potential renal acid load), a low-protein vegetarian diet (LPVD) was designed to enhance the production of bases in body. The aim of this study was to investigate if LPVD has an effect on blood acid–base status and performance during submaximal and maximal aerobic cycling.MethodsNine healthy, recreationally active men (age 23.5 ± 3.4 yr) participated in the study and were randomly divided into two groups in a cross-over study design. Group 1 followed LPVD for 4 days and group 2 ate normally (ND) before performing a cycle ergometer test. The test included three 10-min stages at 40, 60 and 80% of VO2max. The fourth stage was performed at 100% of VO2max until exhaustion. After 10–16 days, the groups started a second 4-day diet, and at the end performed the similar ergometer test. Venous blood samples were collected at the beginning and at the end of both diet periods and after every stage cycled.ResultsDiet caused no significant difference in venous blood pH, strong ion difference (SID), total concentration of weak acids (Atot), partial pressure of CO2 (pCO2) or HCO3- at rest or during cycling between LPVD and ND. In the LPVD group, at rest SID significantly increased over the diet period (38.6 ± 1.8 vs. 39.8 ± 0.9, p=0.009). Diet had no significant effect on exercise time to exhaustion, but VO2 was significantly higher at 40, 60 and 80% of VO2max after LPVD compared to ND (2.03 ± 0.25 vs. 1.82 ± 0.21 l/min, p=0.035; 2.86 ± 0.36 vs. 2.52 ± 0.33 l/min, p<0.001 and 4.03 ± 0.50 vs. 3.54 ± 0.58 l/min, p<0.001; respectively).ConclusionThere was no difference in venous blood acid–base status between a 4-day LPVD and ND. VO2 was increased during submaximal cycling after LPVD suggesting that the exercise economy was poorer. This had no further effect on maximal aerobic performance. More studies are needed to define how nutrition affects acid–base balance and performance.


Journal of Strength and Conditioning Research | 2015

Body composition and power performance improved after weight reduction in male athletes without hampering hormonal balance.

Heikki Huovinen; Juha J. Hulmi; Juha Isolehto; Heikki Kyröläinen; Risto Puurtinen; Tuomo Karila; Krzysztof Mackala; Antti Mero

Abstract Huovinen, HT, Hulmi, JJ, Isolehto, J, Kyröläinen, H, Puurtinen, R, Karila, T, Mackala, K, and Mero, AA. Body composition and power performance improved after weight reduction in male athletes without hampering hormonal balance. J Strength Cond Res 29(1): 29–36, 2015—The aim of this study was to investigate the effects of a 4-week weight reduction period with high protein and reduced carbohydrate intake on body composition, explosive power, speed, serum hormones, and acid-base balance in male track and field jumpers and sprinters. Eight participants were assigned to a high weight reduction group (HWR; energy restriction 750 kcal·d−1) and 7 to a low weight reduction group (LWR; energy restriction 300 kcal·d−1). Energy and carbohydrate intake decreased significantly (p ⩽ 0.05) only in HWR by 740 ± 330 kcal·d−1 and 130 ± 29 g·d−1, respectively. Furthermore, total body mass and fat mass decreased (p ⩽ 0.05) only in HWR by 2.2 ± 1.0 kg and 1.7 ± 1.6 kg, respectively. Fat-free mass (FFM), serum testosterone, cortisol, and sex hormone–binding globulin did not change significantly. Ca2+ ion and pH decreased (p ⩽ 0.05) only in HWR (3.1 ± 2.8% and 0.8 ± 0.8%, respectively), whereas declined (p ⩽ 0.05) in both groups by 19.3 ± 6.2% in HWR and by 13.1 ± 8.5% in LWR. The countermovement jump and 20-m sprint time improved consistently (p ⩽ 0.05) only in HWR, by 2.6 ± 2.5 cm and 0.04 ± 0.04 seconds, respectively. Finally, athletes with a fat percentage of 10% or more at the baseline were able to preserve FFM. In conclusion, altered acid-base balance but improved weight-bearing power performance was observed without negative consequences on serum hormones and FFM after a 4-week weight reduction of 0.5 kg·wk−1 achieved by reduced carbohydrate but maintained high protein intake.


Applied Physiology, Nutrition, and Metabolism | 2017

Dietary acid load and renal function have varying effects on blood acid-base status and exercise performance across age and gender

Enni-Maria Hietavala; Jeffrey R. Stout; Lynda Frassetto; Risto Puurtinen; Hannu Pitkänen; Harri Selänne; Harri Suominen; Antti Mero

Diet composition influences acid-base status of the body. This may become more relevant as renal functional capacity declines with aging. We examined the effects of low (LD) versus high dietary acid load (HD) on blood acid-base status and exercise performance. Participants included 22 adolescents, 33 young adults (YA), and 33 elderly (EL), who followed a 7-day LD and HD in a randomized order. At the end of both diet periods the subjects performed a cycle ergometer test (3 × 10 min at 35%, 55%, 75%, and (except EL) until exhaustion at 100% of maximal oxygen uptake). At the beginning of and after the diet periods, blood samples were collected at rest and after all workloads. Oxygen uptake, respiratory exchange ratio (RER), and heart rate (HR) were monitored during cycling. In YA and EL, bicarbonate (HCO3-) and base excess (BE) decreased over the HD period, and HCO3-, BE, and pH were lower at rest after HD compared with LD. In YA and EL women, HCO3- and BE were lower at submaximal workloads after HD compared with LD. In YA women, the maximal workload was 19% shorter and maximal oxygen uptake, RER, and HR were lower after HD compared with LD. Our data uniquely suggests that better renal function is associated with higher availability of bases, which may diminish exercise-induced acidosis and improve maximal aerobic performance. Differences in glomerular filtration rate between the subject groups likely explains the larger effects of dietary acid load in the elderly compared with younger subjects and in women compared with men.


European Journal of Applied Physiology | 2010

Effects of resistance exercise and protein ingestion on blood leukocytes and platelets in young and older men

Juha J. Hulmi; Tero Myllymäki; M. Tenhumäki; N. Mutanen; Risto Puurtinen; Gøran Paulsen; Antti Mero


SpringerPlus | 2015

Effects of far-infrared sauna bathing on recovery from strength and endurance training sessions in men

Antti Mero; Jaakko Tornberg; Mari Mäntykoski; Risto Puurtinen


Revista de Educación Física | 2014

La Restricción Moderada de Energía con una Dieta Rica en Proteínas Produce un Perfil más Saludable en Mujeres - G-SE / Editorial Board / Dpto. Contenido

Antti Mero; Heikki Huovinen; Olle Matintupa; Juha J. Hulmi; Risto Puurtinen; Hannele Hohtari; Tuomo Karila

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Antti Mero

University of Jyväskylä

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Juha J. Hulmi

University of Jyväskylä

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Heikki Huovinen

University of Jyväskylä

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Olle Matintupa

University of Jyväskylä

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Hannu Pitkänen

University of Jyväskylä

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Harri Selänne

University of Jyväskylä

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Harri Suominen

University of Jyväskylä

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