Recent studies indicate that exercise with a low muscle glycogen state enhances exercise-induced metabolic adaptation. However, it is unclear whether metabolic adaptation is involved with muscle glycogen depletion level. In this study, we investigated the effects of prior muscle glycogen depletion level on metabolic response during acute continuous exercise. Seven men completed two experimental trials consisting of two exercise sessions per day. During the first session, participants performed either intermittent exercise (IE) at VO₂max (the IE-CE trial) or continuous exercise (CE) at lactate threshold (the CE-CE trial). During the second session, participants performed 60 minutes of CE at lactate threshold. During this second session, fatty acid oxidation (FAO) was calculated. To determine muscle glycogen content and PGC-1α and PDK-4 mRNA abundance, muscle biopsies were taken at rest after the first session and 2 hours after the second session. After the first session, muscle glycogen content was significantly lower in the IE-CE trial (38.1±5.0 mmol/kg w.w.) than in the CE-CE trial (56.7±10.2 mmol/kg w.w.), P<0.05. FAO was higher in the IE-CE trial than the CE-CE trial at baseline and 15 minutes after the second session (both P<0.05). PGC-1α mRNA abundance increased after exercise (IE-CE, 5.9±2.5; CE-CE, 2.6±1.3-fold; P<0.1). PDK-4 mRNA abundance increased significantly after exercise (IE-CE, 22.2±8.8; CE-CE, 31.5±10.6-fold; P<0.05). PGC-1α and PDK-4 mRNA were not significantly different between the trials. In conclusion, continuous exercise with a slightly muscle glycogen-depleted state induced similar level of PGC-1α and PDK-4 mRNA expression, but attenuated FAO, compared to exercise with a moderate muscle glycogen-depleted state.

The decrease of muscle glycogen may be useful for the improvement of endurance performance. Intense anaerobic exercise requires a high rate of glycogen utilization, but consecutive intense anaerobic exercises induce a pronounced decline of external power and muscle glycogen consumption. We hypothesized that a long rest period between consecutive intense anaerobic exercises may aid in sustaining external power and glycogen consumption. Secondly, we hypothesized that active rest (AR) during the long resting period may be more effective than passive rest (PR).Six subjects performed four 30-second Wingate tests (WAnT) with a 4-minute recovery between each bout (Consecutive method). The subjects also performed a similar exercise procedure, but with a 30-minute seated resting period after the second bout (PR method).The other six male subjects performed four 30-second WAnTs with a 4-minute recovery between each bout, with 30-minutes of cycling at 40% VO₂max after the second bout (AR method). The subjects also performed PR method.The total work during the third and fourth bouts was greatest under the AR condition, followed by the PR condition, and finally the Consecutive method (p<0.05 for all comparisons). Blood lactate concentration during resting period was significantly lower, while muscle glycogen consumption was greater AR method than PR method (p<0.05 for both).A long resting period between consecutive intense anaerobic exercises may prevent the decline in external power and work. Additionally, AR has more favorable effects on muscle glycogen consumption, resulting in very low muscle glycogen levels, even with a small total amount of exercise.

We report a 41-year-old man who presented with a ruptured dissecting aneurysm of the descending aorta. He had undergone aortic root replacement for an acute aortic dissection (Stanford type A) ; 8 months later, he had undergone total arch replacement with insertion of a frozen elephant trunk (FET) due to enlargement of the chronic dissecting aneurysm of the arch. FET-induced new entry and incomplete thrombosis occurred postoperatively. Three months after FET insertion, he developed an aortic rupture that required emergency replacement of the descending aorta. The patient tolerated the procedure well and was discharged 16 days after the operation.

Bleeding control during aortic surgery is one of the most important issue. The well-known fibrinogen-based hemostat contains the blood product, which means the potential risk of the blood-related infection. Recently, the newly-designed hemostat “Hydrofit”, which is assembled with urethane-based polymer without blood product (Matsudyte : Sanyo-chemical industry, Kyoto, Japan). Hydrofit is applicated for the hemostasis of thoracic aortic surgery. In sealing of the Hydrofit gel to the anastomosis site of aorta, water-contact initiation boosts the chemical change to the forming elastomer and adheres around anastomosis site rapidly. We experienced the extirpation of the Hydrofit which was used over 4 years ago. The patient is 42 year-old female who was operated aortic valve replacement and graft replacement of ascending aorta using a Hydrofit as a hemostat at 4 year 8 months ago due to the aortitis syndrome. Re-sternotomy and re-AVR was performed because of the prosthetic valve dehiscence due to the active aortitis syndrome. Hydrofit left around suture line without infection, and functioned very well as the elastic sealant for the long-term period.