Session Message

{
   message_index: message_index,
   timestamp: date_time,
   event: event,
   event_type: event_type,
   start_time: date_time,
   start_position_lat: sint32,
   start_position_long: sint32,
   sport: sport,
   sub_sport: sub_sport,
   total_elapsed_time: uint32,
   total_timer_time: uint32,
   total_distance: uint32,
   total_cycles: uint32,
   total_strides: uint32,
   total_calories: uint16,
   total_fat_calories: uint16,
   avg_speed: uint16,
   max_speed: uint16,
   avg_heart_rate: uint8,
   max_heart_rate: uint8,
   avg_cadence: uint8,
   avg_running_cadence: uint8,
   max_cadence: uint8,
   max_running_cadence: uint8,
   avg_power: uint16,
   max_power: uint16,
   total_ascent: uint16,
   total_descent: uint16,
   total_training_effect: uint8,
   first_lap_index: uint16,
   num_laps: uint16,
   event_group: uint8,
   trigger: session_trigger,
   nec_lat: sint32,
   nec_long: sint32,
   swc_lat: sint32,
   swc_long: sint32,
   normalized_power: uint16,
   training_stress_score: uint16,
   intensity_factor: uint16,
   left_right_balance: left_right_balance_100,
   avg_stroke_count: uint32,
   avg_stroke_distance: uint16,
   swim_stroke: swim_stroke,
   pool_length: uint16,
   pool_length_unit: display_measure,
   num_active_lengths: uint16,
   total_work: uint32,
   avg_altitude: uint16,
   max_altitude: uint16,
   gps_accuracy: uint8,
   avg_grade: sint16,
   avg_pos_grade: sint16,
   avg_neg_grade: sint16,
   max_pos_grade: sint16,
   max_neg_grade: sint16,
   avg_temperature: sint8,
   max_temperature: sint8,
   total_moving_time: uint32,
   avg_pos_vertical_speed: sint16,
   avg_neg_vertical_speed: sint16,
   max_pos_vertical_speed: sint16,
   max_neg_vertical_speed: sint16,
   min_heart_rate: uint8,
   time_in_hr_zone: uint32,
   time_in_speed_zone: uint32,
   time_in_cadence_zone: uint32,
   time_in_power_zone: uint32,
   avg_lap_time: uint32,
   best_lap_index: uint16,
   min_altitude: uint16
}