Family Hydration

Hydration for tween (ages 12-13) doing track and running

Per EFSA, the total-water target for 9-13 year-olds is 2,100 ml/day for boys and 1,900 ml/day for girls (food plus beverages), with extra fluid added for track training. Running is one of the most cardiovascularly demanding youth sports, and performance declines at as little as 2% body-mass loss.

Quick answer

Hydration for tween (ages 12-13) doing track and running

Per EFSA's 2010 Dietary Reference Values, the total-water Adequate Intake (food plus beverages) for 9-13 year-olds is 2,100 mL/day for boys and 1,900 mL/day for girls. Add fluid for track training and heat: whole-body sweat rates during exercise typically run about 0.5 to 2.0 L/h (Baker 2017), and physical performance declines at as little as 2% body-mass loss (Popkin 2010).

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Tweens (ages 12-13) doing track and running training face a different hydration problem than either the general age group or the general sport. Running is one of the most cardiovascularly demanding youth sports — fluid loss is high, thirst is routinely ignored during training, and physical performance declines at as little as 2% body-mass loss (Popkin 2010). Whole-body sweat rates during exercise typically run about 0.5 to 2.0 L/h across athletes, with higher rates in warm weather (Baker 2017). The longer the session, the more the athlete under-drinks relative to target. Sessions and matches are at full duration; travel teams and club-level intensity begin in this band. Start from the EFSA total-water baseline for this age band — 2,100 ml/day for boys and 1,900 ml/day for girls (food plus beverages) — and add fluid on top to cover the session's sweat loss.

Targets for tweens (ages 12-13) doing track and running training

Training-day baseline for tweens (ages 12-13): 2,100 ml boys / 1,900 ml girls, plus session fluid

The EFSA total-water Adequate Intake for 9-13 year-olds is 2,100 ml/day for boys and 1,900 ml/day for girls (food plus beverages). Track and running training adds fluid on top to cover sweat loss; whole-body sweat rates during exercise typically run about 0.5 to 2.0 L/h (Baker 2017).

Source: EFSA 2010 Water DRV + Baker 2017 sweat-rate review

Pre / during / post — the only framework that matters

Start the session ahead, not catching up. For this age band and sport: a pre-session dose 60-90 minutes before, scheduled sips during, and weight-based replacement after. Non-training days use the age-band baseline only — don't over-drink on rest days.

Urine colour is the cleanest daily signal

Pale straw by the mid-afternoon bathroom visit means the athlete started the session hydrated. Dark yellow or amber before training means a pre-session 500 ml top-up, not 'just start'.

Age maturity: Sessions and matches are at full duration; travel teams and club-level intensity begin in this band.

Match intake to real session length. A preschooler's 'soccer practice' is structurally different from a teen's — don't apply teen protocols to 5-year-olds, and don't apply preschool protocols to competitive tweens.

Practical tips for this age and sport

  • Pre-run: 400-500 ml 60-90 minutes before, topped up 100 ml 15 minutes before starting
  • Runs under 45 minutes: water is enough; runs 45-90 minutes: electrolytes + water
  • Hot-weather runs: 150 ml every 15 minutes minimum, even if it breaks pace
  • Post-run: weigh before/after for a week to find the athlete's sweat rate
  • Tournament weekends: per-match bottle + between-match bottle — non-negotiable
  • Electrolyte drink for any single session over 60 minutes at moderate-to-high intensity

Training-day plan — printable for the sports bag

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When to watch or act

Signs of Dehydration

  • Dizziness on standing after a hard set — immediate stop, 500 ml, no return without clearance
  • Urine darker than light straw before training — pre-session deficit, top up 500 ml before starting
  • Performance drop in the last third of the session — classic hydration signal, not 'being tired'
  • Headache or nausea during or after training — stop, hydrate, don't push through

Sources & Citations

  • 2100 mL/day (2.1 L/day)EFSA total-water Adequate Intake for boys 9-13 years (water from food plus beverages)[1]
  • 1900 mL/day (1.9 L/day)EFSA total-water Adequate Intake for girls 9-13 years (water from food plus beverages)[1]
  • 2% or more body-mass lossPhysical performance declines at as little as 2% body-mass loss; at or above 2% impairs thermoregulation, cardiovascular function and aerobic exercise[2]
  • ~0.5 to ~2.0 L/hWhole-body sweat rate during exercise typically ranges across athletes (with rates above 3.0 L/h in roughly 2% of athletes)[3]
  1. [1]EFSA 2010 Water DRVEFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA). Scientific Opinion on Dietary Reference Values for water. EFSA Journal. 2010;8(3):1459.DOI: 10.2903/j.efsa.2010.1459
  2. [2]Popkin 2010Popkin BM, D'Anci KE, Rosenberg IH. Water, hydration, and health. Nutr Rev. 2010;68(8):439-458.PMID: 20646222DOI: 10.1111/j.1753-4887.2010.00304.x
  3. [3]Baker 2017Baker LB. Sweating Rate and Sweat Sodium Concentration in Athletes: A Review of Methodology and Intra/Interindividual Variability. Sports Med. 2017;47(Suppl 1):111-128.PMID: 28332116DOI: 10.1007/s40279-017-0691-5

Last reviewed: 2026-06-22. Every figure on this page is sourced to the named primary references above.

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Frequently Asked Questions

How much water does a tween kid need on a track and running training day?

Start from the EFSA total-water baseline for this age band — 2,100 ml/day for boys and 1,900 ml/day for girls (food plus beverages) — then add fluid for track training to cover the session's sweat loss. Whole-body sweat rates during exercise typically run about 0.5 to 2.0 L/h.

What's the pre / during / post split for this age and sport?

Pre 400-500 ml in the 90 minutes before, during 200 ml every 15-20 minutes, post 500-600 ml within 30 minutes. Electrolyte drink if the session runs over 60 minutes.

What about sports drinks — does track and running training need them at this age?

For sessions or matches over 60 minutes at moderate-to-high intensity, yes. Otherwise water + a balanced post-session meal is better than a sports drink with added sugar.

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