Which is more optimum to use when adding keys to an object ? - Spread operator with && or ternary if-else operator

Question

Assuming the first_name key is always present in the request body: which is more optimum , method 1 or method 2 ?

const user: any = {}

// Use ternary operator - 1
user.first_name = req.body.first_name ? req.body.first_name : user.first_name

//Or Spread operator with && - 2
user = {
...(req.body.first_name && {'first_name':  req.body.first_name} )
}


user.save()