著者

Naomi YOSHII Koji SATO Riki OGASAWARA Toshiyuki KURIHARA Takafumi HAMAOKA Satoshi FUJITA

出版者

Center for Academic Publications Japan

雑誌

Journal of Nutritional Science and Vitaminology (ISSN:03014800)

巻号頁・発行日

vol.63, no.6, pp.379-388, 2017 (Released:2018-01-12)

参考文献数

47

被引用文献数

6

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Dietary protein intake is critical for maintaining an optimal muscle mass, especially among older individuals. Although protein supplementation during resistance training (RT) has been shown to further augment training-induced muscle mass in older individuals, the impact of daily variations in protein intake on training-induced muscle mass has not been explored thus far. Therefore, this study aimed to investigate the relationship between the dietary protein and amino acid intake and RT-induced muscle hypertrophy among older individuals. Ten healthy older men (n=10; mean age=69±2 y; body weight (BW)=61.5±2.2 kg; height=1.65±0.02 m) participated in progressive RT performed 3 times/wk for 12 wk. Body composition (using DXA) and nutritional assessments (using a 3-d dietary record) were performed before and after the training period. Leg lean mass (LLM) increased significantly (15.0±0.8 vs. 15.4±0.8 kg, p<0.05) after RT, with no change in dietary nutrient intake. The average dietary protein intake was 1.62±0.11 g/kg BW/d, while essential amino acids was 600±51 mg/kg BW/d. Although the correlation between the increase in LLM and dietary protein intake was not significant, a significant correlation was found between the increase in LLM and dietary essential amino acid (EAA) intake. Furthermore, there were significant correlations between the increase in LLM and protein as well as EAA (especially leucine) intake at breakfast among subjects with suboptimal protein intake (p<0.05). Our study findings indicate that dietary protein as well as EAA intake may be significant contributing factors in muscle hypertrophic response during RT among healthy older men.

著者

Masahiro Goto Yoshihiro Yamashina Akihiro Takada Yui Kikuchi Takafumi Hamaoka Shigeru Terada

出版者

The Society of Physical Therapy Science

雑誌

Journal of Physical Therapy Science (ISSN:09155287)

巻号頁・発行日

vol.34, no.4, pp.335-340, 2022 (Released:2022-04-08)

参考文献数

22

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[Purpose] The purpose of this study was to determine the efficacy of using a cold pack while doing resistance exercises for enhancing muscle strength and muscle hypertrophy through decreased intramuscular oxygenation and/or increased myoelectric activity. [Participants and Methods] Twenty-four resistance-trained males (age: 26.4 ± 8.4 years, height: 169.3 ± 5.2 cm, body weight: 74.7 ± 8.8 kg) involved in this study. All the participants completed two experimental sessions in random order (cold pack resistance exercise and resistance exercise) with a 3-day interval. Four types of resistance exercises (4 sets × 8 repetitions with an 8-repetition maximum) targeting the right triceps brachii muscle were performed in both the experimental sessions. [Results] The percentage baseline oxyhemoglobin/myoglobin level during resistance exercise was significantly lower, the half-recovery time of muscle oxygenation in intervals between sets was significantly longer, and the myoelectric activity was significantly higher in the cold pack resistance exercise than in the resistance exercise session. [Conclusion] The results suggest that using a cold pack with resistance exercises is effective in inducing intramuscular deoxygenation and increasing myoelectric activity and may be useful for increasing muscle strength and inducing hypertrophy.

著者

Kana Konishi Tetsuya Kimura Atsushi Yuhaku Toshiyuki Kurihara Masahiro Fujimoto Takafumi Hamaoka Kiyoshi Sanada

出版者

一般社団法人日本体力医学会

雑誌

The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)

巻号頁・発行日

vol.6, no.2, pp.111-117, 2017-03-25 (Released:2017-03-19)

参考文献数

40

被引用文献数

6

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Exercise-induced changes in executive function affect the control of action in a dynamic environment. This study aimed to examine the effect of sustained high-intensity exercise on executive function. Nine healthy male and female participants (age, 21-28 years) completed an exercise session with 65-min treadmill running at 75% VO2max. Executive function was assessed before and after exercise with the Stroop Color and Word Test that included congruent and incongruent conditions. The reaction time and response accuracy of the test were measured, and the task difficulty was controlled by adjusting the stimulus duration so that each participant could maintain at least 80% response accuracy to exclude the effect of a speed–accuracy trade-off. The levels of plasma norepinephrine and adrenocorticotropic hormone were examined. A significant interaction with the reaction time was found (condition × time, P = 0.024), in which the reaction time significantly increased after exercise only in the incongruent condition (P = 0.019). The response accuracy was not significantly different between before and after exercise in both conditions, which indicated that the response accuracy was controlled as intended. The levels of plasma norepinephrine and adrenocorticotropic hormone were significantly increased after exercise (P < 0.05). These results demonstrated that the reaction time in the incongruent condition increased after sustained high-intensity exercise with a cognitive function test with the response accuracy controlled, indicating a decline in executive function. Increased levels of plasma norepinephrine and adrenocorticotropic hormone may contribute, at least in part, to such decline in executive function.

著者

Naoki Horii Natsuki Hasegawa Shumpei Fujie Keiko Iemitsu Masataka Uchida Takafumi Hamaoka Motoyuki Iemitsu

出版者

SOCIETY FOR FREE RADICAL RESEARCH JAPAN

雑誌

Journal of Clinical Biochemistry and Nutrition (ISSN:09120009)

巻号頁・発行日

vol.67, no.3, pp.338-343, 2020 (Released:2020-11-01)

参考文献数

33

被引用文献数

4

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Androgen hormones are important compounds related to body composition and exercise performance in athletes. The intake of Dioscorea esculenta, known as lesser yam, contains diosgenin and resistance training have been shown to normalize the secretion of androgen hormones. This study aimed to clarify the level of androgen hormone secretion and the effects of Dioscorea esculenta intake with resistance training on muscle hypertrophy and strength in athletes. First, in a cross-sectional study, we compared the serum androgen hormone [dehydroepiandrosterone (DHEA), testosterone, and 5α-dihydrotestosterone (DHT)] levels between sprint athletes (n = 15) and non-athletes (n = 15). Second, in an 8-week intervention study, sprint athletes were randomly divided into 2 groups: resistance training with placebo (n = 8) or with Dioscorea esculenta (2,000 mg/day) intake (n = 7). The serum DHEA, free testosterone, and DHT levels were lower in athletes than in non-athletes. Dioscorea esculenta intake combined with resistance training increased the arm fat-free mass, the 1 repetition maximum of deadlift and snatch, and the serum DHEA, free testosterone, and DHT levels, compared with resistance training and placebo intake. The results suggested that Dioscorea esculenta intake combined with resistance training has further effects on muscle hypertrophy and strength in athletes by restoring secretion of androgen hormones.

著者

Yuko Kurosawa Takafumi Hamaoka

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)

巻号頁・発行日

vol.6, no.4, pp.215-217, 2017-07-25 (Released:2017-07-12)

参考文献数

12

被引用文献数

2

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Since the 1990’s, creatine has become one of the most popular supplements in the world for the purpose of increasing skeletal muscle creatine, increasing skeletal muscle mass, and improving the amount of exercise training. The first patient with brain creatine deficiency was reported around the year 2000, and this patient’s severe clinical symptoms - such as impairment of brain function - drove researchers to start focusing more on the brain and related studies. Both in vitro and in vivo studies have shown creatine in the body to cover a wide range of roles including bioenergetic, anabolic, bone remodeling, anti-oxidant, anti-apoptotic, anti-excitotoxic and neuroprotective. In this short review, we introduce recent findings on the effects of creatine supplementation on brain function closely related to mental health, which directly influences the quality of life of elderly people.