def log_heart_rate(opts)
      unless opts[:tracker] && opts[:heart_rate] && opts[:date]
        raise Fitgem::InvalidArgumentError, "Must include :tracker, :heart_rate, and :date in order to lof heart rate data"
      end

      opts[:heartRate] = opts.delete :heart_rate
      opts[:date] = format_date(opts[:date])
      opts[:time] = format_time(opts[:time]) if opts[:time]
      post("/user/#{@user_id}/heart.json", opts)
    end
def log_heart_rate(opts)
      unless opts[:tracker] && opts[:heart_rate] && opts[:date]
        raise Fitgem::InvalidArgumentError, "Must include :tracker, :heart_rate, and :date in order to lof heart rate data"
      end

      opts[:heartRate] = opts.delete :heart_rate
      opts[:date] = format_date(opts[:date])
      opts[:time] = format_time(opts[:time]) if opts[:time]
      post("/user/#{@user_id}/heart.json", opts)
    end
==========================================
        Heart Rate Logging Methods
 ==========================================
 Log heart rate information to fitbit

 @param [Hash] opts Heart rate data
 @option opts [String] :tracker Heart rate tracker name;
   predefined or custom tracker name (matches tracker name on the website) (REQUIRED)
 @option opts [Integer, String] :heart_rate Heart rate measurement (REQUIRED)
 @option opts [DateTime, Date, String] :date Log entry date (REQUIRED)
 @option opts [DateTime, String] :time Time of the measurement; hours and minutes in the format HH:mm

 @return [Hash] Summary of logged information