NHL, Recovery, and a Mountain of Data – Training Insights with Minnesota Wild’s Matt Harder

Matt Harder, head strength and conditioning coach of the Minnesota Wild, shows how he uses rolling weekly training impulse (TRIMP) from heart rate data to decide when NHL players need recovery and when they need extra work, for performance staff in professional hockey.

About this webinar

Matt Harder leads strength and conditioning for the Minnesota Wild. He started as an athletic trainer and worked with the Manchester Monarchs in the ECHL, four years with the Tucson Roadrunners in the AHL, the Arizona Coyotes and the Wild’s AHL affiliate in Iowa. He shows game heart rate reports, the spreadsheet where he tracks daily TRIMP, rolling seven-day sums and the acute to chronic workload ratio, and the formula he uses for players who don’t wear a monitor. In the NHL, wearing a monitor in games is optional for players; about five or six Wild players wore one each game. The session runs 90 minutes and was recorded on 27 June 2023.

What you will learn

• Why a rolling seven-day TRIMP close to or over 1,000 is the point where Harder raises recovery with the head coach
• A game TRIMP estimate for players without a monitor: time on ice × 3.5 plus game length in minutes
• What an average NHL game costs: TRIMP 215, about 11 minutes above 90% of maximum heart rate
• How he tops up scratched players to a daily TRIMP of 100–120
• Why he works to an acute to chronic ratio of 0.8–1.2 rather than 1.5

Practical examples from the recording

1. The weekly number behind a practice off. Harder checks every player’s rolling seven-day TRIMP after games and at the end of each day. The team averages about 840 a week, and he aims to keep players between 500 and 1,000. When several are close to or over 1,000, he texts head coach Dean Evason or stops by his office with the numbers, not an opinion, and the coach decides. For players near 500, he aims 10–15% above their average load over the next seven to 10 days.

2. Estimating game TRIMP without a monitor. Harder’s formula is time on ice in minutes × 3.5, plus total game time. With an average game of 151 minutes, a player on the ice for 16.7 minutes comes out at 209 against a team average of 215. Comparing estimates with measured games, he finds them within about 10 of the real value. Practices without a monitor get the team or position average, so gaps don’t skew the weekly sums.

3. What a game costs. Across his games, average heart rate is 62% of maximum for about two and a half hours, and players spend about 11 minutes above 90%. The average shift this season was 51.5 seconds, and Harder rarely sees a shift that stays under 90%. He reads each report for recovery between shifts and periods: a player who doesn’t drop below 70% in an intermission gets a conversation, which has led to breathing work. The same game profile shapes his off-season intervals, from 90% down to 60–65% and back.

4. Keeping scratched players fit. An average day is about 120 TRIMP. On a game day, a player who isn’t playing should reach over 100 and ideally 120: if the morning skate gives 90, he needs 30 more from the workout and conditioning, done as intervals to 90% and down to 65%. When a player’s weekly TRIMP falls to the low 500s or 400s, Harder plans extra work over the next seven to 10 days, for example 12 intervals from 90% to 60%.

Questions answered in the Q&A

How do you set a weekly TRIMP threshold for players who run hot or cold?
Learn each player’s normal. A player who always hits 120–140 in practice and 250 in a game will reach 990 in a week with three games and two practices. Harder pairs high numbers with a conversation and other tests, such as jumps or grip strength.

If chronic load is high, can a player go over 1,000?
Harder says even adapted players are still pushing it, because 1,000 a week is hard to reach. He uses a 7:28-day acute to chronic ratio with 0.8–1.2 as his window and finds weekly TRIMP easier to work with, since the ratio is volatile.

Is TRIMP lower in the second game of a back-to-back?
Yes, on average about 10% lower, which surprised Harder. He expected the second game to cost more. He now pre-fills each schedule with average game and practice values, so the next week’s load is visible in advance.

Does high weekly load relate to old injuries flaring up?
Anecdotally, yes. Harder can’t show it statistically, but players with past knee, hip or shoulder surgery start to complain when load stays high. One player had been over 900 for six days, so the workout became mobility, sauna and cold tub.

How do you set maximum heart rate for hockey players?
From hard practices in training camp. If a player’s profile says 195 but he reaches only 185 in a bag skate while others are near their maximum, Harder adjusts it. Another option is a treadmill run at 10% incline and speed 10 to failure.

Who this webinar is for

Strength and conditioning coaches, sports scientists and heads of performance in professional ice hockey, plus head coaches and athletic trainers who decide on practice days and recovery through an 82-game season, including for call-ups and scratched players.