Preparing for Game Day: Combining Internal and External Load in American Football

Terrence Kennell, director of applied science for Auburn University football, shows how he combines heart rate and GPS data to set practice loads and prepare players for an up-tempo offense, for performance staff in college football.

About this webinar

Terrence Kennell joined Auburn in December after three-plus years at the University of South Florida, where he first brought heart rate monitoring into the program, and earlier work in rugby and soccer in the UK. He shows what a game costs offensive and defensive linemen, receivers and defensive backs, how low, medium and high practice days look in heart rate zones, and how his summer week is built around TRIMP and high-speed distance targets. He also covers energy expenditure for the dietitian, players who respond differently to the same practice, and how he reports to position coaches. The session runs 57 minutes and was recorded on 3 September 2026.

What you will learn

• What a game costs linemen: training impulse (TRIMP) up to 438 and 24–61 minutes at threshold and above
• The TRIMP targets for each summer day, from 60–70 on a tempo day to 190–200 plus on the two big days
• How green, orange and red practice days give position coaches a shared language for load
• Why two corners with the same reps and high-speed distance can show very different TRIMP
• How one sheet per position group shows coaches which practice periods to pull back

Practical examples from the recording

1. What a game costs a lineman. Accelerometer load told Kennell little about his linemen: a Tuesday and a Wednesday practice could both read 400 while the work was very different. Heart rate did. Across his top seven offensive and top six defensive linemen, game time at threshold and above ranged from 24 to 61 minutes, and TRIMP reached 438 in games with 85 or more plays. That cost shaped how the staff design conditioning and the high practice days for the big guys.

2. A summer week built on TRIMP. The summer block ran 10 weeks: six on, a week off, four on. Monday’s tempo run targets TRIMP of 60–70. Tuesday and Friday are the big days, with TRIMP pushing 190–200 plus and 600–700 yards of high-speed distance. Wednesday’s small-sided work is longer but lower, at 150 or so, and Thursday’s repeat sprint session is only 7–10 minutes of actual work. By week six the staff target 22,000 yards total and 2,700 yards of high-speed distance for the week.

3. Calories the dietitian can use. Heart rate based energy expenditure goes to the dietitian and medical staff. One 200 lb safety burned 2,300 calories in a practice; another player burned 1,900 in a two-hour practice at 185 lb. With sweat testing showing a loss of nine and a half pounds in one practice, the nine or 10 heaviest sweaters now get fluids, snacks and electrolytes during practice, and players see why they need to eat more.

4. Two corners, same work, different cost. Two cornerbacks play the same reps, the same plays in every team period and the same high-speed distance, yet one, who Kennell says naturally runs hot, always has a much higher TRIMP. In games their numbers are more even. Because he is two years older and has had knee surgery, the staff give him more rest when he is off the field, and Kennell says it has worked so far.

Questions answered in the Q&A

Which load metric did you stop trusting?
Accelerometer-based load. At South Florida a player could show 600 and nobody could say what he had done. Kennell prefers metrics with context: high-speed distance shows space to run, and accelerations and decelerations show a tight, small-space day.

How should a football program start with heart rate monitoring?
Start with the linemen. For the first three to four months only offensive and defensive linemen wore monitors. Kennell used their data to suggest task-specific conditioning, such as shorter rest in individual drills to raise intensity toward game level.

How do you report load data to position coaches?
Heart rate and GPS run live in practice, with a list of flagged players. After practice each position coach gets one sheet with TRIMP, distance, high-speed distance and a period breakdown, so he can see the hardest periods and choose where to pull back.

If you could track only three metrics, which would they be?
High-speed distance, acceleration and deceleration load, and TRIMP. Kennell mostly uses total TRIMP, and checks TRIMP per minute on high days, where he expects 1.1 or more.

Do you change the lift after a hard practice?
Yes. In camp the staff have scrapped a lift for a recovery session, cut squats from working up to 80% to 65%, dropped accessory work from three sets to two, or switched accessories to isometrics.

Who this webinar is for

Directors of sports science, sports scientists and strength and conditioning coaches in college and professional American football, plus head and position coaches, dietitians and return-to-play staff who plan practice weeks and need to know what practice and games cost each position group.