(1) The purpose of the present study was to investigate the significance of anaero-bic energy release in two groups of distance runners whose maximal aerobic power was known to be comparable (Vo₂max averaged 71.1±1.22 ml/kg· min) but differed each other significantly in their performance of 5, 000m run (group A ; n=6, timed in average 14'50″1±11″0 ; and group B ; n=6, timed in average 15'52″5±14″1) .
(2) Twelve runners were subjected to 3 experimental series of treadmill running 1, exhaustive running, 2, two to four trials' of submaximal runnings for 15 min, and 3. running at the intensity corresponding to 90% of maximal oxygen uptake for 14 min, then the“last spurt”for 1 min at 120% of maximal oxygen uptake. In addition, they were asked to sprint up a staircase with their top speed.
(3) Exhaustive running time on the treadmill and maximal oxygen debt in group A were 8'56″2±40″8 and 8454±923.7 ml, respectively. Both were significantly larger than 8'02″8±31″0 and 6787±1301.7 ml registered by group B (p<0.05) .
(4) Differences between A and B groups in their cardio-respiratory responses during maximal treadmill running, threshold of anaerobic metabolism, anaerobic power, alactic and lactic oxygen debt, maximal lactate concentration, etc. were found to be not significant.
(5) These results indicate that the variance in maximal oxygen debt may exert a modifying influence in either positive or negative directions which could be the reason why the same level of aerobic power does not guarantee a comparable performance level in actual running event.

Purpose: This study investigated the relationship between the number of days that hospital visits were postponed and changes in clinical parameters due to the spread of coronavirus disease 2019 (COVID-19), after the Japanese government declared a state of emergency in April 2020. Methods: Regarding the status of postponement of appointments, we analyzed the patients who had visited the Nihon University Hospital at Matsudo for more than 1 year for supportive periodontal therapy (SPT) and classified them into low-, moderate- and high-risk subgroups according to the periodontal risk assessment (PRA). Clinical parameters for periodontal disease such as probing depth (PD), full-mouth bleeding score (FMBS), full-mouth plaque score, periodontal inflamed surface area (PISA), and periodontal epithelial surface area (PESA) were analyzed in 2 periods, from October 2019 to March 2020 and after April 2020.Correlation coefficients between days of deferral and the degree of changes in clinical parameters were calculated. Results: The mean age of the 749 patients was 67.56±10.85 years, and 63.82% were female.Out of 749 patients, 33.24% deferred their SPT appointments after April 2020. The average total of postponement days was 109.49±88.84. The number of postponement days was positively correlated with changes in average PD (rs=0.474) and PESA (rs=0.443) in the high-risk subgroup of FMBS, and average PD (rs=0.293) and PESA (rs=0.253) in the highrisk subgroup of tooth number (TN). Patients belonging to the high-risk subgroups for both FMBS and TN had a positive correlation between postponement days and PISA (rs=0.56). Conclusions The findings, the spread of COVID-19 appears to have extended the visit interval for some SPT patients. Moreover, longer visit intervals were correlated with the worsening of some clinical parameters for SPT patients with high PRA.