The basketball player told US website TMZ: "I am not the person that they are making me out to be. Nobody got followed, nobody got hassled, nobody got harassed, nobody got grabbed on."
Khloé Kardashian and Lamar Odom in happier times
He added that he was upset that Khloé hadn't defended him over the incident. According to the sportsman, her silence forced him to speak out.
Looking angry and emotional, he said: "The dog has to bite back. (People have accused me of being) a womaniser, a drug addict."
However, witnesses reported to the site that Lamar was seen shouting at his ex. She apparently ignored him and kept walking. Then Lamar supposedly grabbed her arm.
Khloé is said to have screamed: "Get off of me. Get off of me. Stop. Stop. How did you know that I was here?"
People reports that the reality princess has stopped taking her ex-husband's calls - which is why he tried to surprise her.
"It made Khloé first shocked and then scared that Lamar was waiting outside the studio," a source told the magazine. "She doesn't know how he found her. She is thinking about getting a bodyguard."
Two years after separating following allegation of drug use and infidelity on his part, the couple finally signed their divorce papers last month.
Khloé has moved on, dating another basketball player James Harden, who accompanied her to a birthday dinner for her little sister Kylie Jenner. The Kardashian clan recently turned out in force to celebrate the baby of the bunch's 18th, at which she was presented with a Ferrari.
Her friend Malika Haqq posted a picture of the duo kissing at the party. Previously, they spent the 4 July weekend together and attended a class at SoulCycle.