Text changing back to original after 'swap' function Swift - ios

Question

I'm a bit stumped on this :
Context
I have a 'workout session' which is in a tableView inside a UIViewController. Each cell has an exercise name, number of reps and a swap button. The swap button generates a new exercise from the exercise bank (i.e. if it says "bench press" but you don't have a bench press then you can swap it for something else).
Problem
My swap button code works and a new exercise populates the cell. However, when I press "Play" on my workout timer, it resets to what it was before!
Code - swap button
func swapButtonTapped(cell: WorkoutCell) {
let realmExercisePool = realm.objects(ExerciseGeneratorObject.self)
let index = Int(arc4random_uniform(UInt32(realmExercisePool.count)))
let newExercise = realmExercisePool[index].generateExercise()
cell.exerciseName.text = newExercise.name
cell.repsNumber.text = String(newExercise.reps)
}
Code - Timer
#IBAction func timerControlTapped(_ sender: UIButton) {
if isTimerRunning == false {
sender.setImage(#imageLiteral(resourceName: "timerPause"), for: UIControlState.normal)
runTimer()
isTimerRunning = true
swapButtonEnabled = false
workoutTableView.reloadData()
} else {
sender.setImage(#imageLiteral(resourceName: "timerPlay"), for: UIControlState.normal)
workoutTimerObject.invalidate()
isTimerRunning = false
}
}
Code - Run Timer
func runTimer() {
workoutTimerObject = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(WorkoutViewController.workoutTimer), userInfo: nil, repeats: true)
isTimerRunning = true
}
The original group of exercises are passed in an array of workoutExercises from the previous VC (a 'workout set up screen')
Thanks everyone!

Answer 1

For anyone else who has a similar problem, I managed to work this out.
This was happening because I was simply changing the 'content' of the cell in my swapButtonTapped and not the actual data source.
When I then called "reloadData()" in timerControlTapped, it was reloading the original data.
What I needed to do was replace the actual data by replacing the exercise at the selected index with a new one in the "selectedWorkoutExerciseArray".
I used this code :
func swapButtonTapped(cell: WorkoutCell) {
let myIndexPath = workoutTableView.indexPath(for: cell)
let realmExercisePool = realm.objects(ExerciseGeneratorObject.self)
let index = Int(arc4random_uniform(UInt32(realmExercisePool.count)))
let newExercise = realmExercisePool[index].generateExercise()
selectedWorkoutExerciseArray[(myIndexPath?.row)!] = newExercise
cell.exerciseName.text = newExercise.name
cell.repsNumber.text = String(newExercise.reps)
}