Cape Town - Speculation over President Jacob Zuma's health was a topic of conversation on Twitter on Tuesday evening after he spent a week resting from an exhausting election programme.

Tuesday's state-of-the-nation address was the president's first public engagement since

Many Twitter users commented on how Zuma's voice sounded and his physical appearance.

“#SONA2014 As someone who listens to voices very carefully, I can't help but feel Zuma's voice is not as powerful as it normally is,” Eyewitness News reporter Stephen Grootes wrote on Twitter.

ENCA's Nickolaus Bauer also commented on Zuma's voice: “#SONA We always read too much into these sort of things... But is it only me that hears the crackle in #Zuma's voice?”

City Press's Carien du Plessis wrote: “Zuma's voice sounds very very tired and even sad, but FF Plus gets him laughing by greeting him in Afrikaans #SONA2014”

Ranjeni Munusamy tweeted: “President Zuma looks noticeably thinner, voice quivering a bit. Not sure he is “frail” though. #SONA2014”.

On Zuma's appearance others said he looked tired.

?(at)OmenMchunu wrote: “President #Zuma looks emotionally and physically strained. Sick in actual fact. I wish him a speedy recovery. Maybe it's time to step down.”

Another user (at)sbo_k said: “President Zuma looks tired and worn out nje #sona2014”

“Why sideline Ramaphosa when Zuma doesn't look so well. Preventing public appraisal?,” (at)EazeyO said.

“Zuma doesn't look so good. He looks tired and weak. #StateOfTheNation,” said another.

Moneyweb editor Ryk van Niekerk wrote: “Is it only me?…Zuma really looks tired. Not someone that was on “leave” for a week. #SONA”

Zuma was discharged from a Pretoria hospital on June 8 after spending a night there. African National Congress secretary general Gwede Mantashe at the time said that Zuma, 72, went for a routine health check.

Mantashe said the ANC's election campaign had been punishing and all senior members of the party would take time off one after another to “re-energise”.

Zuma had taken time off to rest leaving many of his duties in the hands of Deputy President Cyril Ramaphosa.

Sapa