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If you’ve ever done strength training or high-intensity interval training (HIIT) workouts, you may have heard coaches talk about the importance of “time under tension.” This refers to the amount of time your muscles spend contracted during each exercise. The longer your muscles are under tension, the more muscle fibers get recruited and the more growth stimulus occurs. This is why it’s better to do slower, controlled movements rather than quick, sloppy reps when strength training.

I first learned about the concept of time under tension a few years ago when I started getting into HIIT workouts. These workouts involve short bursts of intense exercise followed by brief rest periods. The trainer would always emphasize holding each movement for a certain count—often shooting for around a 30-40 second window for each exercise. This extended time with my muscles contracted and loaded was absolutely exhausting! But it also led to noticeable gains in strength and endurance after just a few weeks.

The same idea applies to traditional strength training. If you speed through bicep curls by flinging the weight up, you won’t stimulate your biceps as effectively as if you do the movement in a slow, controlled fashion taking 3-4 seconds to raise and lower the weight. More time under tension equals more muscle breakdown and more growth as your body adapts.

So what does all this talk about fitness have to do with improving at chess? While chess is a mental game, the concept of time under tension can still be applied to your study efforts. Rather than trying to cram through as many puzzles or play as many blitz games as possible, there is a lot of benefit to spending meaningful time calculating variations, analyzing positions, and thinking deeply about ideas.

I notice that when I really spend 30-45 minutes intently focused on a chess concept or set of positions, I retain that knowledge much better compared to quick pattern recognition through puzzle rush. It’s like weight training for my chess brain! Getting in quality repetition where I’m spending time visualizing the board, calculating variations, and trying to understand plans/motifs does wonders for improving my chess “fitness.”

On the other hand, playing lots of blitz or obsessively trying to set a new puzzle rush record generally doesn’t lead to meaningful improvement. I’m relying on instinct and not really pushing my brain to grow. There’s a place for faster chess, but it shouldn’t be the main focus of your study if you want to maximize your rate of progress.

Here are some ways you can incorporate time under tension into your own chess improvement efforts:

When solving puzzles, take at least 2-3 minutes per puzzle to calculate all variations, not just spot the first move.

Analyze master games move-by-move, pausing for 5-10 minutes on key positions to imagine how you’d approach it over the board.

Pick a strategic theme to focus on like pawn structures or piece placement. Spend 30-45 min examining related examples from games or books.

Work on calculation training. Spend 20-30 minutes visualizing a position in your mind and calculating concrete variations as far as possible.

Study an opening deeply over a period of weeks/months, continually returning to key positions and ideas. Time builds understanding.

The most dramatic leaps in your chess ability will likely come from extended sessions of serious, focused study—not frenzied blitz sessions. So be mindful of how you spend your time at the board or chess screen. Opt for quality over quantity by structuring your study to get in longer periods of “time under tension.” Your understanding and tactical vision will improve much faster if you dedicate real time to serious training.