Commercial Fixed Wing
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Training / Qualification; Human-Machine Interface; Communication Breakdown; Distraction; Fatigue
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Flight Crew Became Reoriented
Environment - Non Weather Related; Human Factors
While descending via the ZZZZZ2 STAR into ZZZ; we were given a direct; followed by a heading and a descent to 6;000 feet and a request to fly our best forward speed for spacing.  In complying with the instructions; I descended below 10;000 feet at 300 knots.  At approximately 9;000 feet; I recognized the error; leveled off and slowed to 250 knots.  We continued the flight to an uneventful landing.Although I had gotten a full night's sleep the night before; I was feeling somewhat fatigued by the time we began the flight to ZZZ.  I had been flying long days from the previous 4 day trip that started with a very early commute on the morning.  Compounding this is the fact that my recency of experience is lacking.  I had flown very little during the previous 3 months due to a problem with my international qualifications.I believe that if I had not gotten distracted with the revised clearances from ATC this would not have happened.  I had been flying in VNAV; but opened the speed window when a higher airspeed was requested by ATC.  My improper monitoring of the automation led me to descend below 10;000 feet at a speed above 250 knots.  Unfortunately; my First Officer did not catch the error either.
Air carrier Captain reported exceeding 250 knots below 10;000 feet during descent. Captain cited fatigue and lack of flying as contributing factors.