public async Task <IActionResult> PostExercise([FromBody] PostExerciseDto exerciseDto)
        {
            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState.Values));
            }

            var postedExercise = await _exercisesService.CreateExercise(exerciseDto.ToExercise());

            if (postedExercise == null)
            {
                return(BadRequest());
            }

            return(StatusCode(201, postedExercise));
        }