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Summary To test the applicability of postexercise blood flow restriction (PEBFR) in practical training programmes, we investigated whether PEBFR enhances muscle hypertrophy induced by multiple-set high-load resistance exercise (RE). Seven men completed an eight-week RE programme for knee extensor muscles. Employing a within-subject design, one leg was subjected to RE + PEBFR, whereas contralateral leg to RE only. On each exercise session, participants performed three sets of unilateral knee extension exercise at approximately 70% of their one-repetition maximum for RE leg first, and then performed three sets for RE + PEBFR leg. Immediately after completion of the third set, the proximal portion of the RE + PEBFR leg was compressed with an air-pressure cuff for 5 min at a pressure ranging from 100 to 150 mmHg. If participants could perform 10 repetitions for three sets in two consecutive exercise sessions, the work load was increased by 5% at the next exercise session. Muscle thickness and strength of knee extensor muscles were measured before and after the eight-week training period and after the subsequent eight-week detraining period. There was a main effect of time but no condition × time interaction or main effect of condition for muscle thickness and strength. Both muscle thickness and strength increased after the training period independent of the condition. This result suggests that PEBFR would not be an effective training method at least in an early phase of adaptation to high-load resistance exercise.

Background: Asian national teams have not performed well compared to American and European teams at international competitions in basketball, possibly due in part to anthropometric disadvantages such as shorter height and wingspan. However, although anthropometric disadvantages exist in women as well as in men, Asian women have shown better performances in international competitions than Asian men. Therefore, Asian women might have developed unique strategy and tactics which would be reflected in game-related statistics. Objectives: This study aimed to investigate whether game-related statistics which discriminate winners from losers in women’s basketball differ between Asian and European competitions. Methods: A total of 108 games from the 2011, 2013 and 2015 FIBA Asia Women’s Championships were analyzed for Asian competitions, and a total of 178 games from the 2011, 2013 and 2015 FIBA EuroBasket Women were analyzed for European competitions. All games were classified into three types (balanced, unbalanced and very unbalanced) according to point differential by a k-means cluster analysis. A discriminant analysis was performed to identify game-related statistics which discriminate winners from losers in each game type. An absolute value of a structural coefficient (SC) equal to or above 0.30 was considered relevant for the discrimination. Results: Successful 2-point field goals discriminated winners from losers independent of the region or game type. Assists discriminated winners from losers except balanced games in Europe. Defensive rebounds discriminated winners from losers only in Europe. Conclusions: The most notable difference between Asian and European women’s basketball was that defensive rebounds discriminated winners from losers in European but not in Asian competitions. It was suggested that losers in Asian games tended to lose ball possession before attempting field goals, and thus reducing opportunities for winners to get defensive rebounds.

Background: Basketball is one of the most popular sports in the world. However, men’s national teams of Asian countries have not performed well at world-level competitions such as Olympic and world cup games. Clarifying the feature of Asian basketball games would be some help to improve the competitiveness of Asian teams. Objectives: This study aimed to identify game-related statistics which discriminate between winning and losing teams in Asian men’s basketball competitions. In addition, European competitions were also analyzed and the results were compared between Asian and European competitions. Methods: A total of 179 games from the 2011, 2013 and 2015 FIBA Asia Championships were analyzed for Asian competitions, and a total of 259 games from the 2011, 2013 and 2015 FIBA EuroBasket were analyzed for European competitions. All games were classified into three types (balanced, unbalanced and very unbalanced) according to point differential. A discriminant analysis was performed to identify game-related statistics which discriminate between winning and losing teams. Results: In European competitions, 76% of the games were classified into balanced games and none of the games was classified into very unbalanced games. In Asian competitions, on the other hand, only 48% of the games were classified into balanced games and 15% of the games were classified into very unbalanced games. In balanced games, defensive rebounds and assists discriminated between winning and losing teams in Asian competitions whereas defensive rebounds did so in European competitions. In unbalanced games, successful 2-point field goals, defensive rebounds and assists discriminated between winning and losing teams in both Asian and European competitions. Conclusions: Asian competitions had higher proportions of unbalanced and very unbalanced games than European competitions. However, a discriminant analysis, which was performed independently for each type of game, showed similar results between Asian and European competitions. The only difference was observed in balanced games’ assists which discriminated between winning and losing teams in Asian competitions but not in European competitions.

We previously reported that low-intensity [50% of one repetition maximum (1RM)] resistance training with slow movement and tonic force generation (LST) causes muscle hypertrophy and strength gain in older participants. The aim of this study was to determine whether resistance training with slow movement and much more reduced intensity (30%1RM) increases muscle size and strength in older adults. Eighteen participants (60-77 years) were randomly assigned to two groups. One group performed very low-intensity (30% 1RM) knee extension exercise with continuous muscle contraction (LST: 3-s eccentric, 3-s concentric, and 1-s isometric actions with no rest between each repetition) twice a week for 12 weeks. The other group underwent intermitted muscle contraction (CON: 1-s concentric and 1-s eccentric actions with 1-s rest between each repetition) for the same time period. The 1RM, isometric and isokinetic strengths, and cross-sectional image of the mid-thigh obtained by magnetic resonance imaging were examined before and after the intervention. LST significantly increased the cross-sectional area of the quadriceps muscle (5.0%, P

Low-intensity resistance exercise can effectively induce muscle hypertrophy and increases in strength when combined with moderate blood flow restriction (BFR). As this type of exercise does not require lifting heavy weights, it might be a feasible method of cardiac rehabilitation, in which resistance exercise has been recommended to be included. Although previous studies with healthy subjects showed relative safety of BFR exercise, we cannot exclude the possibility of unfavourable effects in patients with cardiovascular disease. We therefore aimed to investigate haemostatic and inflammatory responses to BFR exercise in patients with ischaemic heart disease (IHD). Nine stable patients with IHD who were not taking anticoagulant drugs performed four sets of knee extension exercise at an intensity of 20% one-repetition maximum (1RM) either with or without BFR. Blood samples were taken before, immediately after and 1 h after the exercise session and analysed for noradrenaline, D-dimer, fibrinogen/fibrin degradation products (FDP) and high-sensitive C-reactive protein (hsCRP). Plasma noradrenaline concentration increased after the exercise, and the increase was significantly larger after the exercise with BFR than without BFR. On the other hand, increases in concentrations of plasma D-dimer and serum hsCRP were independent of the condition. However, increases in D-dimer and hsCRP were no longer observed after plasma volume correction, suggesting that hemoconcentration was responsible for these increases. Plasma FDP concentration did not change after the exercise. These results suggest that applying BFR during low-intensity resistance exercise does not affect exercise-induced haemostatic and inflammatory responses in stable IHD patients.

The purpose of this study was to investigate the role of muscle metaboreflex on exercise-induced growth hormone (GH) secretion. In order to accumulate metabolites within exercised muscle with minimized central motor activity, electromyostimulation (EMS) was performed combined with blood flow restriction (BFR). Seven men performed one-legged isometric knee extension evoked by EMS (frequency, 20 Hz; pulse duration, 400 μs; on-off ratio, 3-1 s). Just before the exercise, proximal portion of either a stimulated thigh (ST) or a non-stimulated thigh (NT) was compressed at 150 mmHg with an air-pressure cuff for the purpose of BFR. The compression was kept throughout the exercise session, and was released 2 min after the end of the exercise. Two exercise sessions (ST(BFR), BFR for ST; NT(BFR), BFR for NT) were separated by 1 week. ST(BFR) was aimed to accumulate metabolites within exercised muscle, whereas NT(BFR) was aimed to match mechanical stress with ST(BFR) without accumulating metabolites. Blood samples for hormonal measurements were taken from the antecubital vein before and after the exercise. Blood lactate increased immediately after the exercise in the NT(BFR), whereas it increased after the cuff deflation in the ST(BFR), suggesting that locally produced metabolites were retained and accumulated within the exercised muscle in the ST(BFR). Although serum cortisol and plasma noradrenaline increased in a similar manner in two conditions, serum immunoreactive GH (irGH) increased only in the ST(BFR). These results suggest that muscle metaboreflex plays an important role in the exercise-induced GH secretion, at least in terms of irGH secretion.

High-intensity exercise shares similarities with acute phase responses of inflammatory diseases. We investigated the influences of acute exercise on inflammatory markers, plasma pentraxin3 (PTX3) and serum high-sensitive C-reactive protein (CRP) (hsCRP). Nine healthy male subjects (41 ± 3 years old) participated. Each subject performed three types of exercise; ergometer exercise at 70% workload of anaerobic threshold (AT) for 30 min (70% AT exercise), peak ergometer exercise (peak EX, 20 watt increase/min until fatigue) and resistance exercises of 70% 1 RM (70% RE) until exhaustion. We measured plasma PTX3, serum hsCRP, lactate, noradrenaline (NOR), white blood cells (WBC), interleukin-6 (IL-6) and myeloperoxidase (MPO), a marker of neutrophil degranulation. The effects of exercise on intracellular PTX3 and MPO in neutrophils were also investigated, by using flow cytometry analysis. Circulating PTX3 and hsCRP significantly increased immediately after 70% RE and peak EX, while they did not increase after 70% AT exercise. The exercise-induced fold increase in PTX3 and hsCRP relative to the resting level was positively correlated with the changes in WBC, NOR, lactate and MPO. The exercise-induced fold increase in IL-6 was positively correlated with that in NOR, but not with that in PTX3 and hsCRP. Neutrophils isolated immediately after 70% RE, but not 70% AT exercise, exhibited lower mean fluorescence for PTX3 and MPO than those from pre-exercise blood. These results provide the evidence that high-intensity exercises significantly increase circulatory PTX3 as well as hsCRP. The release from peripheral neutrophils is suggested to be involved in the exercise-induced plasma PTX3 increase.

Recent studies have demonstrated that even a low-intensity resistance exercise can effectively induce muscle hypertrophy and strength increase when combined with moderate blood flow restriction (BFR) into the exercising muscle. Although serious side effects of low-intensity resistance exercise with BFR have not been reported, a concern of thrombosis has been suggested, because this type of exercise is performed with restricted venous blood flow and pooling of blood in extremities. Thus, the purpose of this study was to investigate the effects of low-intensity resistance exercise with BFR on coagulation system in healthy subjects. Ten healthy men (25.1 +/- 2.8 year) performed four sets of leg press exercises with and without BFR (150-160 mmHg) at an intensity of 30% of one-repetition maximum (1RM). In each exercise session, one set with 30 repetitions was followed by three sets with 15 repetitions. Blood samples were taken before, and 10 min, 1, 4 and 24 h after the exercise. Prothrombin fragment 1 + 2 (PTF) and thrombin-antithrombin III complex (TAT) were measured as markers of thrombin generation, whereas D-dimer and fibrin degradation product (FDP) were measured as markers of intravascular clot formation. Changes in plasma volume (PV) were calculated from haemoglobin and hematocrit values. PV reduction was significantly greater after the exercise with BFR than without (P

KAATSU training induces muscle hypertrophy and strengthens muscle in athletes and healthy subjects through short-term and low-intensity exercise. However, it remains uninvestigated whether lowintensity KAATSU resistance training (LIKRT) induces muscle strength and hypertrophy in patients with cardiovascular diseases. We examined the effects of LIKRT on skeletal muscle size/strength and endurance capacity in patients with ischemic heart disease (IHD). Seven male patients with stable IHD performed three kinds of resistance exercises (leg press, leg curl and leg extension) with their femoral muscle blood flow restricted by KAATSU belt two times/week for three months. We measured one RM (1-RM) in each resistance exercises, and evaluated muscle cross-sectional areas (CSA) by MRI before training and after the training. We used cardiopulmonary examinations to measure endurance capacity (Peak VO2 (VO2peak), VO2 at anaerobic threshold (VO2AT)). We performed blood sampling to measure resting plasma level of insulin growth factor-1 (IGF-1) and serum high-sensitive C-reactive protein (hsCRP). LIKRT significantly increased leg press (15%), leg curl (18%) and leg extension (17%) 1-RM strength. Increases of muscle CSA in quadriceps femoris at the proximal lower leg (30%), the mid-thigh (50%), and the proximal lower leg (70%) were 5.1%, 4.6% and 10.4%, respectively. Similarly, hamstring and adductor CSA were also increased by LIKRT. LIKRT significantly increased VO2peak and VO2AT by 10.7% and 10.9%, respectively. IGF-1 and hsCRP were not altered before or after the training. These results suggest that LIKRT increases muscle strength/mass and endurance capacity in patients with IHD. LIKRT appears to be a promising and effective resistance method in cardiac rehabilitation.

The present study investigated whether circuit training with body weight alone (no external load) can cause muscular hypertrophy when combined with moderate venous occlusion (‘Kaatsu Training’). Healthy women (mean age, 32.7 ± 4.0 yr; n=22) were randomly assigned into the occlusive training group (OCC, n=11) and the normal training group (NOR, n=11). Both groups performed the same circuit-training regimen consisting of six, successive exercises for muscles in the upper and lower limbs and the trunk, at a frequency of 3 sessions/wk. Each session lasted for 5-10 min. In OCC group, proximal ends of the upper and lower limbs of both sides were moderately compressed by means of ‘KAATS Sportswear’, to restrict the venous blood flow during the exercises (preset pressure, 50-80 mmHg and 80-120 mmHg for upper and lower limbs, respectively). Cross-sectional area (CSA) of the thigh muscle was measured with spiral computer tomography. After an 8-wk period of training, the muscle CSA of both right and left limbs showed significant increases by ∼3% (P

We investigated the acute effects of “Kaatsu” resistance exercise and other types of exercise on muscle oxygenation and plasma growth hormone. Six young male bodybuilders performed leg extension exercise according to four exercise regimens: low-intensity [∼30% of one repetition maximum (1RM)] exercise with moderate occlusion (LO-Kaatsu), low-intensity (∼50% 1RM) exercise with slow movement and tonic force generation (3 s for lowering and 3 s for lifting actions, 1-s pause, and no relaxing phase; LST), low-intensity (same as LST) isometric exercise at 45° knee angle (ISO), and high-intensity (∼80% 1RM) exercise with normal movement speed (HN), commonly used for gaining muscular size and strength. The muscle oxygenation level measured with near-infrared continuous-wave spectroscopy (NIRcws) showed the largest changes during and after LO-Kaatsu among all regimens. The minimum oxygenation level during LO-Kaatsu was the lowest among the four exercise regimens. On the other hand, the increases in muscle oxygenation after LO-Kaatsu were the largest among the four regimens. Plasma GH and blood lactate concentrations after LO-Kaatsu, LST and HN were significantly (P < 0.05) higher than those after ISO, but there were no significant differences among those after LO-Kaatsu, LST and HN. The results indicate that “Kaatsu” resistance exercise causes marked changes in muscle oxygenation level and circulating growth hormone, both of which may be related to muscular hypertrophy.

The purpose of this study was to investigate the effect of blood flow-restricted training (BFRT) on jump performance in relation to changes in muscle strength. Seventeen untrained young men were assigned into either BFRT or normal training (NORT) groups and performed low-intensity [30-40% of one-repetition maximum (1RM)] resistance exercise (horizontal squat, 3-4 sets × 15-30 repetitions) twice a week for 10 weeks. The BFRT performed the exercise with their proximal thighs compressed by air-pressure cuffs for the purpose of blood flow restriction. Squat 1RM, muscle cross-sectional area (CSA) of quadriceps femoris, and countermovement jump (CMJ) height were measured before and after the 10-wk training period. Squat 1RM increased greater in BFRT than in NORT (19.3% vs. 9.7%, P < 0.01). Although the CSA increase was independent of groups, it tended to be larger in BFRT than in NORT (8.3% vs. 2.9%, P = 0.094). On the other hand, CMJ height did not change after the training (P = 0.51). In conclusion, the present study showed that BFRT induced muscle hypertrophy and strength increase, whereas it did not increase CMJ height in previously untrained young men. It is suggested that BFRT is ineffective in improving jump performance.

To compare endocrine responses to low-intensity resistance exercise with blood flow restriction (BFR) for upperlimb (UL) and lower-limb (LL) muscles, we measured blood lactate, plasma noradrenaline, and serum growth hormone (GH), testosterone, cortisol and insulin-like growth factor-I (IGF-I) before and after the UL (biceps curl and triceps press down) and LL (leg extension and leg curl) exercises with BFR in nine men (26.3 +/- 3.1 yr). The load of 30% of one-repetition maximum (1RM) was used in all the exercises, in which the first set of 30 repetitions was followed by the second and third sets to failure. In each exercise program, the proximal portions of their upper arms (UL) or thighs (LL) were compressed bilaterally by elastic belts. Both the UL and LL caused significant increases in lactate, noradrenaline, GH, testosterone, cortisol, and IGF-I concentrations when compared to the pre-exercise values. A significant difference between the UL and LL was observed only in the area under the curve (AUC) of serum GH concentration, indicating that the LL induced greater GH response than did the UL. The greater GH secretion following the LL may be more advantageous for muscle hypertrophy induced by a long-term training period.

Purpose: This study investigated whether muscle hypertrophy-promoting effects are cross-transferred in resistance training with blood flow restriction, which has been shown to evoke strong endocrine activation. Methods: Fifteen untrained men were randomly assigned into the occlusive training group (OCC, N = 8) and the normal training group (NOR, N = 7). Both groups performed the same unilateral arm exercise (arm curl) at 50% of one-repetition maximum (1RM) without occlusion (three sets, 10 repetitions). Either the dominant or nondominant arm was randomly chosen to be trained (OCC-T, NOR-T) or to serve as a control (OCC-C, NOR-C). After the arm exercise, OCC performed leg exercise with blood flow restriction (30% of 1RM, three sets, 15-30 repetitions), whereas NOR performed the same leg exercise without occlusion. The training session was performed twice a week for 10 wk. In a separate set of experiments, acute changes in blood hormone concentrations were measured after the same leg exercises with (N = 5) and without (N = 5) occlusion. Results: Cross-sectional area (CSA) and isometric torque of elbow flexor muscles increased significantly in OCC-T, whereas no significant changes were observed in OCC-C, NOR-T, and NOR-C. CSA and isometric torque of thigh muscles increased significantly in OCC, whereas no significant changes were observed in NOR. Noradrenaline concentration showed a significantly larger increase after leg exercise with occlusion than after exercises without occlusion, though growth hormone and testosterone concentrations did not show significant differences between these two types of exercises. Conclusion: The results indicate that low-intensity resistance training increases muscular size and strength when combined with resistance exercise with blood flow restriction for other muscle groups. It was suggested that any circulating factor(s) was involved in this remote effect of exercise on muscular size