Some Russians are casting doubt on a recent report that the 60-year-old Putin caught a 21-kilogram pike during a trip to the Tyva region in Siberia earlier this month.

Despite assurances from the Kremlin that the story is true, some are doubting the reported size of the fish and whether it was Putin himself who actually reeled in the pike on the July 20 trip.

Even video and photos of the president, decked out in khakis and camouflage while proudly holding the large pike have not quieted Russians from suggesting the stunt was a hoax.

Putin is well-known for publicly participating in outdoorsy, daring adventures in a bid to boost his strong image.

From hang gliding to deep sea diving, here's a look at some of Putin's exploits:

1. In September 2012 Putin took flight in a motorized hang glider in Russia's northern Yamal region, during a mission to save the rare Siberian white crane.

(AP / RIA-Novosti, Alexei Druzhinin, Presidential Press Service)

2. The president is reported to be a black belt in judo. In 2008 Putin, who was the Russian prime minister at the time, even released an instructional judo DVD to coincide with his 56th birthday.

(AP / RIA Novosti, Alexei Druzhinin, Government Press Service)

3. A spokesperson for the then-prime minister admitted in 2011 that the discovery of fragments of an ancient Greek jug by Putin during a diving expedition was, in fact, staged.

Spokesperson Dmitry Psekov told local media that the fragments – which Putin claimed to have discovered with "the boys" in about six feet of clear water -- had been found earlier by archaeologists and strategically placed for the leader to find.

(AP / RIA Novosti, Alexei Druzhinin)

4. In 2010 Putin travelled to Russia's arctic north to visit a research institute, where he helped fix a radio beacon on the neck of a giant polar bear. According to reports, the bear had been captured 10 days ahead of Putin's visit and had been sedated just before his arrival.

(AP / RIA Novosti, Alexei Nikolsky, Government Press Service)

5. In 2011, Putin rode front and centre with the Nochniye Volki (Night Wolves) biker group during a bikers' festival in the Black Sea city of Novorossiysk.

(AP / RIA Novosti, Alexei Druzhinin)

With files from The Associated Press