A study was performed to clarify the relationships between oxygen uptake (VO₂) kinetics on recovery from incremental maximal exercise and blood lactate, glucose and alanine metabolism. Eight healthy males aged 21.6±3.3 years were studied. The incremental exercise test was performed using a modified version of Bruce's protocol until 30 min after exhaustion. The VO₂ responses on recovery were fitted by a two-component exponential model. Blood lactate concentration in the recovery phase was fitted by a bi-exponential time function to assess the velocity constant of the slowly decreasing component (γ2) expressing the rate of blood lactate removal. Both blood lactate and plasma alanine concentration were significantly increased from rest to maximal exercise, and were significantly decreased thereafter, but remained above resting values for 30 min after the maximal stage. Blood glucose concentration was significantly decreased following maximal exercise and returned to the pre-exercise value by 30 min after the maximal stage. Concentrations of plasma branched-chain amino acids (valine, leucine and isoleucine) were significantly decreased from the maximal stage until 30 min after exhaustion. The time constant of the slow component on recovery VO₂ [τVO₂ (s) ] was correlated with neither γ2 nor the degree of change in blood lactate from the maximal stage until 30 min after exhaustion (Δlactate) . However, τVO₂ (s) was significantly correlated with both Δ blood glucose and Δ alanine. In addition, Δ alanine was significantly correlated with Δ blood glucose. From these results, we conclude that oxygen uptake kinetics after exhaustive maximal exercise is related to glucose resynthesis through alanine metabolism, as compared with that from lactate metabolism.

A study was performed to clarify the effects of endurance training above the anaerobic threshold (AT) on the isocapnic buffering phase during incremental exercise in athletes. Eight middle-distance runners aged 19.6±1.2 years performed incremental exercise testing with a modified version of Bruce's protocol. After a 6-month high-intensity interval and paced running training at levels above AT, maximal oxygen uptake (VO₂max) (ml⋅ kg^-1⋅min^-1) was significantly increased from 60.1±5.7 to 64.7±5.5 (p<0.05) . AT (m⋅lkg^-1⋅min^-1) was slightly but significantly increased from 28.2±3.5 to 29.6±4.3 (p<0.05) . The respiratory compensation point (RC) (ml⋅ kg^-1⋅min^-1) was markedly increased from 53.0±8.3 to 57.7±8.2 (p<0.05) . Although neither the slope of the first regression line below AT (S1) nor that of the second line above AT (S2) calculated by V-slope analysis was altered, the range of isocapnic buffering (ml⋅kg^-1⋅min^-1) from AT to RC was significantly extended from 24.8±5.9 to 28.1±6.0 after the 6-months of training (p<0.05) . In addition, the amount of change in VO₂max after the 6-month of training period (ΔVO₂max) was correlated with Δisocapnic buffering (R=0.72, p<0.05) . We conclude that the degree of increased respiratory compensation point is larger than that of AT after high-intensity endurance training at levels above AT, and that the range of isocapnic buffering may be an important factor in relation to the increase in the maximal aerobic capacity of athletes.

A study was conducted to establish a method for quantitative evaluation of both the rate and degree of muscle oxygenation during ramp exercise using Near Infrared Spectroscopy (NIRS), and to determine the relationship of the indices to body composition and physical fitness. The subjects were 13 healthy men. After a warm-up period of 3 min at 20-W, the ramp exercise test was conducted. The exercise consisted of an increasing work rate at a slope of 20 W/min on a cycle ergometer performed until volitional fatigue. The NIRS probe used in the cycling exercise was placed on the vastus lateralis muscle. After 30 min of exercise, calibration was performed by cuff occlusion for 10 min with a pressure of 260 mmHg for quantitative determination of the NIRS curve. The oxygenation curve measured by NIRS during the exercise initially exhibited a linear decrease as the work rate increased. This rate of decrease in oxygenation was indicated by the NIRS slope (%/W) obtained from the calibration curve. In later stages of the exercise, the NIRS curve became flattened with increased work rate. The breaking point between the sloping phase and the flat phase was named the “NIRS Threshold 2, NT 2”. In addition, the rate of decrease in oxygenation at the end of exercise per maximal NIRS decrease obtained from the calibration curve was indicated as the %NIRS fall. The mean NIRS slope and %NIRS fall were 0.3±0.1%/W (range, 0.13 to 0.50%/W) and 29.9±11.8% (range, 12.0 to 50.0%), respectively. NT 2 was observed in 8 of the 13 subjects. The subjects were divided into two groups (NT 2 (+) and NT 2 (-) ) based on the appearance of NT 2. Both the NIRS slope and %NIRS fall in the NT 2 (+) group were significantly higher than those in the NT 2 (-) group. The NIRS slope was significantly correlated with VO₂/wt at VT (r=0.73, p<0.05) and wattage at VT (r=0.86, p<0.0001) . The %NIRS fall was significantly correlated with VO₂/wt at peak (r=0.80, P<0.001) . The NIRS slope and %NIRS fall were not significantly correlated with body mass index, %fat or thigh circumference.
These findings suggest that the NIRS slope indicates the efficiency of oxygen exchange in muscles activated during incremental exercise, and that the %NIRS fall indicates the ability to utilize Oxy-Hb+Mb against maximal oxygenation capacity in muscles. The NIRS slope and %NIRS fall can therefore be used as indices of muscular limitation during exercise, and as indices of muscular adaptation during exercise.

The purpose of this study was to confirm both the reproducibility of indices (NIRS slope, NT2, %NIRS fall) and the specificity obtained by analyzing the muscle oxygenation curve measured by near-infrared spectroscopy (NIRS) during ramp exercise. Ten healthy men participated in this study. The NIRS probe was placed on the vastus lateralis muscle. An increase in oxygenation was observed from rest to warm-up at 0 watts (Δ NIRS) . Oxygenation began to decrease lineally as the workload increased (NIRS slope) . In the latter phase of exercise, the oxygenation curve flattened out despite an increasing workload, and as a result, an inflection point was formed (NT2) . The minimum value of oxygenation during ramp exercise was indicated as“%NIRS fall.”
Protocol 1. After a warm-up period of 3 min at 0 watts, a ramp exercise (20 watt/min) test was performed until volitional fatigue. The test was performed for each subject twice (test-1, test-2) with a 1-week interval. Protocol 2. A test was performed with three consecutive ramp exercises (lOwatt/min·20watt/min·30watt/min) up to120watt each with sufficient rest between the exercises.
NT2 was observed in 7 of 10 subjects. Test-1 and test-2 mean values of ANIRS, NIRS slope, watts at NT2 (NT2) and %NIRS fall were not significantly different, and the correlations between test-1 and test-2 were highly significant (r=0.94, P<0.0001: ANIRS, r=0.99, P<0.0001: NIRS slope, r=0.91, P<0.002: NT2 and r=0.78, P<0.005 : %NIRS fall) . The regression lines obtained for correlations of results of test-1 and test-2 were y=-5.89+1.38X (Δ NIRS), y=0.02+ 1.03X (NIRS slope), y=31.52+0.83X (NT2), and y=19.91+0.61X (%NIRS fall) . No significant differences in both intercept and coefficient between the regression line and identity line were found in the NIRS slope and NT2. The rate of decrease in the oxygenation curve became steeper with an increase in work-load from 10 watts/min to 20 watts/min and to 30 watts/min. However, the mean values of the NIRS slope, modified by watts, were 0.29±0.06%/watt, 0.29±0.07%/watt and 0.29±0.07%/watt, respectively. There were no significant differences of the NIRS slopes among these exercises. The results indicate constancy of the rate of decrease in oxygenation per workload.
In conclusion, these findings demonstrate the reproducibility of the NIRS slope and the appearance of NT2 during ramp exercise, and the specific way in which the decrease in muscle oxygenation reflects workload. They suggest that analysis of the muscle oxygenation curve can be used to estimate muscular metabolism and indices of training effects.

Objective：The aim of this study was to examine the relationships between the timing of gait acquisition and the length of hospitalization, and to clarify the differences in background factors and functional recovery during the early postoperative period and their effect on the variability in gait acquisition.
Methods：We recruited 148 patients who underwent total knee arthroplasty (TKA) at three hospitals. The participants were divided into two groups on the basis of the number of days needed to achieve independent gait at ≤14 days after surgery (group A) and ＞14 days after surgery (group B). We compared the background factors between the two groups. Additionally, we compared the preoperative and postoperative function in each group.
Results：We observed a significant positive correlation between the number of days needed to achieve independent gait and the length of hospitalization. In group A, the significant background factors were younger age and higher preoperative activity level. In group A, compared with the level of preoperative function, the postoperative maximum knee extension angle on the operated side and pain had significantly improved. In both groups, the postoperative knee extensor strength on the operated side, knee extensor strength on the nonoperated side, knee flexion strength on the operated side, maximum knee flexion angle on the operated side, and walking speed were significantly reduced.
Conclusion：During early rehabilitation, it is necessary to consider the age and previous activities of patients. In addition, we suggest that early rehabilitation with a focus on reducing pain by alleviating inflammation and improving maximum knee extension angle on the operated side may be effective for fast acquisition of gait.

Objective：To elucidate factors associated with physical function and clarify the actual condition of functional deterioration in patients with knee osteoarthritis (OA) prior to total knee arthroplasty (TKA)．

Methods：We enrolled 467 patients with severe knee OA and preoperatively assessed the following parameters：background factors (sex, age, BMI, K-L grade, and pain) and physical function (muscle strength of knee extensors and flexors, and knee joint angles). A multiple regression analysis was performed to determine the relationship between the independent background factors and dependent physical functions. The median of preoperative function based on selected factors of physical function was calculated.

Results：Based on the multiple regression analysis, sex, BMI, K-L grade, and pain statistically significantly correlated with muscle strength of knee extensors and flexors. Sex and BMI statistically significantly correlated with knee joint flexion angle. K-L grade statistically significantly correlated with knee joint extension angle. The median of muscle strength for knee extension was 0.98/0.92 Nm/kg (Grade 3/Grade 4) for males and 0.70/0.59 Nm/kg for females. The median of muscle strength for knee flexion was 0.53/0.45 Nm/kg for males, 0.36/0.30 Nm/kg for females. The median for knee joint flexion angle was 130° for males and 120° for females. The median for knee joint extension angle was -5°/-10° (Grade 3/Grade 4)．

Conclusion：We clarified the degree of muscle strength and range of motion before TKA in patients with knee OA. We believe that the findings obtained in this study will contribute to explaining the functional deterioration of patients with knee OA.

　　It is said that diabetes is one of the factors contributing to the onset of dementia and accelerating its progression. The number of dementia cases is expected to increase steadily year by year. Such being the circumstances, we encountered an elderly woman with diabetes and dementia, who managed to lower her blood glucose values to a proper level somehow or other, thus lightening the burden of caregivers. We shall hereby report the case because we thought it would make a good example for care in the region where the population is rapidly graying. The woman, then at age 80, visited our hospital complaining of languidness. Her blood sugar level was so high (random blood glucose level: 1,096 mg/dl) that she was hospitalized at once. By a stepwise insulin reinforcement therapy, the blood glucose levels were under control. During the stay in hospital, she was also diagnosed as having senile dementia. She was provided with effective health care and education for the control of blood sugar levels. Having snacks between meals was strictly prohibited. Considering that she was an elderly person living alone, only internal medicines were given. As a result, her blood glucose levels were elevated to about 300 mg/dl, but the combined use of GLP-1 injection and internal medicine once a week had good control over blood glucose levels. So, the patient was discharged from the hospital.

　　A 63-year-old woman was admitted with complaints of thirst and polyuria about 1 year after ceasing therapy in November, X and in October, X+1. Her blood glucose levels at the beginning of her admissions were 347 at the first admission and 486 at the second admission. We administered glargine, a long-acting type insulin, 8U/day, and　a short-acting insulin, glulisine, 4U/day, during the first admission. We administered glargine, a long-acting type insulin, 4U/day, and a short-acting insulin, glulisine, 3U/day, during the second admission. We also administered a GLP-1 receptor agonist, liraglutide, 0.3mg/day. Blood glucose levels (mg/dl) during the 5 days of the first admission were as follows: first, -, -, 347, and 180; second, 273, 266, 109, and 188; third, 75, 192, 186, and 182; fourth, 93, 194, 91, and 144; fifth, 78, 95, 124, and 127. In the second admission, blood glucose levels were as follows: first, -, -, 486, and 299; second: 140, 137, 195, and 128; third: 101, 122, 114, and 108; fourth: 101, 123, 123, and 137; and fifth, 89, 136, 111, and 129. CGM data showed an average of 128mg/dl and standard deviation of 34 during the first admission. CGM data showed an average of 125mg/dl and standard deviation of 20 during the second admission. The reduction of insulin and rapid flattening of blood sugar were achieved by GLP-1 receptor agonist with promotion of insulin secretion and suppression of glucagon secretion.

Background/Aims: Inflammatory bowel disease (IBD) is a chronic inflammation of the gastrointestinal tract. Some patients with this condition have been reported to present with immunoglobulin A nephropathy (IgAN), a renal complication that can cause end-stage renal failure, but the frequency of this comorbidity has not been described. Thus, the aim of this study was to investigate the frequency of IgAN in patients with IBD. Methods: This study included 620 patients with IBD (338 with ulcerative colitis [UC] and 282 with Crohn’s disease [CD]) from the Hiroshima University Hospital outpatient department. IgAN cases were identified from medical interviews, blood examinations (serum immunoglobulin A), and urinalyses (occult blood, proteinuria). Definitive IgAN cases were diagnosed by renal biopsies, while those detected through the clinical course and test results, but not clinically recommended for renal biopsy, were defined as suspected IgAN. Results: We analyzed 427 cases meeting the inclusion criteria (220 with UC and 207 with CD). The incidence of IgAN across all patients with IBD was 3.0%. The frequency of IgAN was significantly higher in patients with CD (11/207, 5.3%) than in those with UC (2/220, 0.9%) (P< 0.01). Moreover, a significant correlation was found between CD patients with ileostomy or colostomy and a diagnosis of IgAN. Conclusions Patients with IBD present a high incidence of IgAN, especially those with CD who have undergone ileostomy or colostomy.