The effect of L-ornithine hydrochloride ingestion on human growth hormone secretion after strength training

This study aimed to examine the effect of L-ornithine hydrochloride ingestion on serum growth hormone secretion response after strength training in young men who did not regularly engage in high intensity exercise. Ten healthy young males without workout habits (age: 22.2 +/- 1.0 yr). Subjects performed biceps curl strength training after L-ornithine hydro- chloride and placebo ingestions. They participated in both of the above conditions randomly with a week interval in between. Serum growth hormone and ornithine levels were measured before L-ornithine hydrochloride or placebo ingestions and at 30 minutes after strength training. Serum growth hormone and ornithine level were measured. A change magnitude of serum growth hormone was significantly larger in the L-ornithine hydrochloride condition than in the placebo condition, and the effect size was also large (t = 1.91, p = .044, ES = .75). A significant interaction (F = 280.98, p = 0.000, ηp2 = 0.96) was found in serum ornithine and a multiple comparison test showed that it was greater in the L-ornithine hydrochloride condition. Serum growth hormone level after strength training increases by L-ornithine hydrochloride ingestion in untrained young males.

Reliability of a new rapid step test for older women and its relationship with fall risk and leg muscle function

This study aimed to examine trial-to-trial reliability of a new clinical test, rapid reaction step cued on a screen test, and its relationship with fall risk score, independence in activity of daily living score, and various leg muscle function tests. One-hundred fifty seven older women participated in this study. Nine square plates (32 × 32 cm) were lined up with three plates. Participants stood on a center plate and were instructed to step, using one leg, to one of the other eight plates, as quickly as possible, when that plate changed in color from white to red. The mean total time and the mean total error time of rapid reaction step cued on a screen and, fall risk score, activity of daily living score, lower muscle function (isometric muscle strength: toe flexion, plantar flexion, knee extension, hip flexion;balance: one leg standing time with eye open, functional reach test;gait: 10 m walk time with maximal speed). Results: trial-to-trial reliabilities of step parameters were high (intraclass correlation coefficient [ICC] = 0.75 - 0.85). The step parameters correlated significantly with the other parameters except for toe flexion and hip flexion strengths. In conclusion, the present step test was found to evaluate physical function related to prevention of falls in older people.

Influence of degraded visual acuity from light-scattering goggles on obstacle gait

This study examined the effect on gait of de-grading visual input by simulation on a course with obstacles. Thirty healthy, young adult males walked on a 6 m path with three obstacles (height: 5, 10, 20 cm, width: 10 cm) set at inter-vals of 150 cm with and without degraded visual input from light-scattering goggles. Gait was examined with respect to time, length, angle and walk speed parameters. Gait changed signifi-cantly in the degraded visual input condition. The distances between the obstacles and foot before the obstacles were significantly larger in 10 and 20 cm obstacles under the degraded visual input condition, but distances after passing the obstacle had no significant difference among obstacle height. We therefore conclude that a decrease of visual function alters the perception of an obstacle’s height, particularly the 5 cm height obstacle.

Comparison of strength values and laterality in various muscle contractions between competitive swimmers and untrained persons

Competitive swimmers may gain a specific training effect as the result of long term exercise in the water. This study aimed to compare isometric, non-isokinetic and isokinetic muscle strengths in competitive swimmers and untrained persons. Twelve young male adults without exercise experience for over three years and twelve swimmers with over 10 years of competitive swimming experience performed various strength tests. Non-isokinetic tests were evaluated using one repetition of maximum half squat, vertical jump, and drop jump. Isometric and isokinetic (60 and 180 deg/s) muscle strengths were measured by both legs in knee extension and flexion. There were no significant differences between non-isokinetic and isometric muscle strengths of both groups. On the other hand, all isokinetic parameters in both angular velocities were significantly larger in competitive swimmers. There was significant laterality of isokinetic strength in untrained persons, but not in competitive swimmers. In addition, right and left differences of isokinetic strength tended to be smaller in competitive swimmers. In conclusion, competitive swimmers tended to be superior only in isokinetic strength, which is a similar muscle contraction in the water, and have less right and left differences.

Slow movement resistance training in women

A resistance training protocol of low intensity and short duration allows for increased training frequency and improved compliance. This study aimed to examine the short-term (response of growth hormone (GH) and testosterone after one exercise session) and long-term (change of fitness level and body fat percentage after the exercise period) effects of slow movement resistance training using the individual’s body mass (hiroNARI style training) in adult women and to clarify their subjective sense of training continuity. Nineteen healthy adult women performed hiroNARI style training three times a week for 12 weeks. This protocol consisted of 12 types of exercise for 7 muscle groups. GH and testosterone increased significantly after one exercise session (70% and 23.3%, p < 0.05, respectively). Height and the circumferences of the upper arm (flexed), chest, waist, hip, and thigh changed significantly. Except for the upper arm circumference, these parameters improved significantly after 6 weeks. There were significant improvements in measurements of physical fitness after 6 weeks including one leg raise with eyes closed, side step, and repeated sit ups for 30 s. After 12 weeks, anteflexion from a long sitting position improved as well. Triglycerides and HDL and LDL cholesterol changed significantly after 12 weeks. In conclusion, resistance training may have positive effects and is associated with high compliance. However, it will be necessary to reexamine the training protocol for increasing back and lower limb muscle strength and necessary variations to prevent overtraining of certain muscle groups.

Comparison of stepping parameters and center of foot pressure properties during different tempo stepping movements

This study was designed to examine the trial-to-trial reliability of stepping parameters and to compare the center of foot pressure (COP) when adapting to different tempos. Twenty healthy men (M age = 20.8, SD = 1.9 years) performed stepping tests to fixed tempos. The intra-class correlation coefficients of stepping and COP parameters were high (0.75 - 0.97). The time difference between foot contact time and fixed tempo and COP sway velocities of the X- and Y-axis were the largest at 40 beats per minute (bpm). At 60 and 120 bpm tempos, single support and swing times reflecting the stepping strategy correlated significantly with the root mean square and the velocity of the X-axis (r = I0.45 - 0.53I) . Because these step tempos are controlled largely by the automation of stepping, the single support and swing phases appeared to have a constant frequency. On the other hand, a stepping tempo of 40 bpm showed the largest sway velocity of X and Y and the smallest surrounding area mean path length. The above suggests that stepping at 40 bpm induced a larger sway area in relation to total path length and faster COP sway. Hence, it is inferred that the stepping task becomes more difficult at 40 bpm than at 60 and 120 bpm.

Relationship between Extent of Coffee Intake and Recognition of Its Effects and Ingredients

This study examined the relationship between number of cups of coffee intake and recognition of the effects of coffee intake and its ingredients in young males and females. The subjects included 624 young people (ages 15 - 24;359 males, 265 females), who drank coffee habitually. They were classified into three groups on the basis of the number of cups of coffee consumed per day: “one cup,” “two cups,” and “over three cups.” In males, about 25% of the “over three cups” group expected “resolution of stress” from coffee, and this percentage was higher than that in the other groups. In females, about 18% of the same group had similar expectations;however, no significant group difference was found among the three groups. Few persons expected protective effects of diabetes mellitus and cancer in both genders (about 5% answer rate). About 20% of males and 18% of females in the “over three cups” group recognized the “laxative property” of coffee intake, and a significant group difference was found only in males. Even in the “one cup” group, over 77% knew that “caffeine” is an ingredient of coffee;however, few persons (under 15%) knew “poly-phenol,” which has protective effects of diabetes mellitus and cancer. In addition, no significant group difference was found in both genders. In conclusion, regardless of the coffee intake cup-number in both genders, recognition of the effects of coffee intake was low in both males and females and the recognition of effects differs by the intake cup-number in males. Only few persons knew the other ingredients in coffee apart from “caffeine.”

The effect of ornithine ingestion on carbohydrate metabolism during rest after acute resistance exercise in healthy young males

The effect of oral L-ornithine hydrochloride (0.1 g/kg BW) on energy expenditure during a rest period from 120 to 180 min after resistance exercise was evaluated by indirect calorimetry. Healthy male subjects who have no habit of resistance training underwent resistance exercise (chest press, lat pulldown, leg press, shoulder press, leg extension, and leg curl), with 3 sets of each exercise and 10 repetitions in each set at 90-s intervals, 30 min after ingestion of ornithine or placebo. Plasma ornithine levels immediately after, and 120 and 180 min after, resistance exercise were significantly greater after ingestion of ornithine than of placebo (Treatment: F = 347.1, P p2 = 0.95;Interaction: F = 160.7, P p2 = 0.95), but no significant difference in serum growth hormone levels was observed between the two treatments (Treatment: F = 0.1, P = 0.751, ηp2 = 0.01;Time: F = 1.7, P = 0.229, ηp2 = 0.16;Interaction: F = 2.4, P = 0.155, ηp2 = 0.21). Although there was no between-treatment difference in energy expenditure during the rest period 120 to 180 min after resistance exercise (Treatment: F = 0.1, P = 0.718, ηp2 = 0.02;Time: F = 0.1, P = 0.767, ηp2 = 0.01;Interaction: F = 0.1, P = 0.112, ηp2 = 0.26), with ornithine ingestion carbohydrate oxidation was significantly greater than with placebo from 170 to 180 min after exercise (Treatment: F = 0.8, P = 0.383, ηp2 = 0.09;Time: F = 9.7, P = 0.013, ηp2 = 0.52;Interaction: F = 5.8, P = 0.039, ηp2 = 0.39). Moreover, 180 min after exercise, serum free fatty acid levels after ornithine ingestion were lower than after placebo (Treatment: F = 0.3, P = 0.602, ηp2 = 0.03;Time: F = 34.6, P p2 = 0.79;Interaction: F = 5.6, P = 0.042, ηp2 = 0.38). A similar trend in 3-hydroxybutylate was observed. In conclusion, ornithine ingestion before resistance exercise may enhance post-exercise carbohydrate oxidation without changing total energy expenditure.

L-ornithine hydrochloride ingestion increased carbohydrate oxidation but not lipid oxidation during submaximal endurance exercise following resistance exercise

This study aimed to examine the effect of L-ornithine hydrochloride ingestion on lipid oxidation during submaximal endurance exercise following resistance exercise. Ten healthy young male adults with no history of regular resistance exercise (age: 26.0 +/- 4.4) conducted resistance exercise after L-ornithine hydrochloride or placebo ingestion (0.1 g/kg). Subjects exercised for 60 min on an ergometer at 50% VO2peak 120 min after resistance exercise. Plasma ornithine concentrations measured immediately, 120min and 180min after resistance exercise in the L-ornithine hydrochloride ingestion condition were significantly greater than those in the placebo condition. No significant difference was found in serum growth hor mone concentrations between both conditions (F = 4.4, p = 0.065). Serum free fatty acid concentrations were significantly greater immediately after submaximal ergometer bicycle exercise in both conditions than those before ingestion, immediately after resistance exercise and 120min after resistance exercise (F = 43.4, p .001, 300% - 508%), but no significant difference was found between both conditions (F = 3.6, p = 0.090). A similar trend was observed in serum ketone bodies as well. Although total energy production during submaximal ergometer exercise did not significantly differ (t = 0.74, p = 0.238), a significant difference was found in energy production via carbohydrate and lipid oxidation;the former was greater in the Lornithine hydrochloride ingestion condition (t = 1.89, p = 0.046, d = 0.44, 106%), and the latter was greater in the placebo condition (t = 1.89, p = 0.046, d = 0.78%, 145%). From the above, L-ornithine hydrochloride ingestion may not affect lipid metabolism during submaximal endurance exercise following resistance exercise. It may be involved in energy production via carbohydrate oxidation with glucogenic amino acid.

Relationships between gait properties on soft surfaces, physical function, and fall risk for the elderly

The plantar aspect change caused by contact with soft surfaces creates and unstable gait and increases the risk of falling, especially in the elderly. This study aimed to analyze gait property by three-dimensional motion analysis on soft and normal surfaces and to clarify the relationship with physical function and fall risk. Twenty-four older people aged 65-88 years old and living independently without any assistive device (7 men, 17 women) performed 5 m of walking with own maximal speed on normal and soft surface walkways. The soft surface walkway used was a low rebound urethane foam mattress. The three-dimensional kinematic gait analysis by sixteen anatomic points was used to evaluate gait property on both walkways. The gait property on soft surfaces tended to be swinging up and down in each joint and to largely lean left and right as compared with the normal surface. Moreover, it tended to decrease in a step length and to increase in a step width. All gait parameters on soft surfaces correlated significantly with functional reach. On the other hand, that on normal surface correlated significantly with leg strength. Gait properties on soft surfaces which changes in plantar aspect during foot contact differs from those on normal surfaces. Walking on soft surfaces may cause an unanticipated inverted pendulum sway supporting a foot contact point because of the disturbance by a sagging walkway;in short, requiring more effort to keep a body balanced. In conclusion, gait on the soft surfaces requires balance ability (functional reach) rather than leg strength.

Age and Gender Differences in the Step Test with Stipulated Tempos

This study examined differences in tempos of a step test with a stipulated tempo by age levels and gender. Subjects were 316 healthy males and females in the age range of 10 - 80 years. They performed the step test twice for 20 seconds, stepping alternately while a beeping metronome was adjusted to 40 bpm, 60 bpm, and 120 bpm. It was assumed that if the total time discrepancy between the tempos when the foot was grounded was small, people could adjust their steps to different tempos well. The results of a three-way ANOVA showed a significant age difference at 40 bpm. A multiple comparison showed that the total time discrepancy was smaller in 10 - 50 years old than in 60 - 80 years old in males and females. The total time discrepancy at 40 bpm was larger than that at 120 bpm in 10 - 50 years old, and larger in the order of 40, 60, and 120 bpm in 60 - 80 years old. The total time discrepancy showed insignificant gender differences at all ages and tempos. In conclusion, people over 60 years were less able to adjust their steps to a slow tempo than people younger than 50 years. Further, it was more difficult for people under 60 years to adjust their steps to a slower tempo, and a difference in tempos in people over 70 years largely affected their step movements.