The 84-year-old presenter is having a pre-arranged mid-series break from the BBC One dance show on November 10, prompting fresh speculation about his long-term future as the programme's anchor.
Speaking about Forsyth's break from the show, Horwood told Digital Spy: "He's taking a break before Wembley. He's on his feet for 12 or 15 hours a day. Which is a lot for someone who is 84, you know? To maintain strength and all of that, I think it's good that he takes a week out and gears up for the big Wembley show.
"There's an awful lot of pressure for him with that big audience at Wembley and it's a huge deal, so I think it's a really good thing that he does take a break."
When asked if the series could carry on without Forsyth at the helm, he added: "Yes, the show goes to 49 countries worldwide and Brucie isn't on in every country. It works as a format with our without him.
"The format is so strong. I'm not saying you could get anyone up there to do it - and following Brucie brings extra expectations.
"The great thing about Brucie is that he's a song-and-dance man, he's from the London Palladium era and he brings that heritage with him onto the show. He'll be very, very difficult to replace, let's put it like that."
Tess Daly and Claudia Winkleman will team up when Forsyth is absent later this month. Pro dancer Anton Du Beke, Daly's husband Vernon Kay and John Barrowman are among the presenters tipped by bookmakers to replace Forsyth if he retires from the show.
Strictly continues this Saturday (November 3) on BBC One.