The hang-glider flight with the cranes, which took place just before a summit in Vladivostok, was one of Putin's trademark adventurous media events. Yet on the first day of the summit, Putin did seem to be in discomfort as he greeted leaders and avoided standing for long periods of time.
Peskov was quoted as saying that Putin was making only infrequent trips to the Kremlin lately because he didn't want his motorcade to disrupt Moscow's notoriously bad traffic.
That's a laugh — although it is true that Putin's presidential motorcade forces the shutdown of large stretches of highway, an inconvenience that many irritated drivers mark by blaring their horns angrily as his car races past.
Putin has also put off several expected trips abroad, including ones to India, Turkey and Bulgaria. The Interfax news agency cited Peskov as saying there was no single reason behind those changes.
Despite the canceled trips, Putin is still shown on state television almost daily — mostly sitting at meetings with officials.
A Moscow-based political analyst said the health problems of Russian leaders in the past have often led to political crises.
"First of all, it slows everything down. Even the most immediate problems or solutions cannot be taken and they have to be delayed," said Viktor Kremenyuk of the U.S.-Canada Institute. "There is no mechanism to replace the president in the absence of the president. This simply means a standstill — everything stops."
Putin's macho image is especially important in Russia, which has often been ruled by aged autocrats whose health was routinely kept a top secret.
Russians often ascribed Boris Yeltsin's disjointed speech and bizarre behavior to heavy drinking, although his press service insisted he was taking strong drugs to alleviate a heart condition.