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Science & Research

Kafein Pra‑Latihan Nambah Kekakuan Arteri, Bubuk Bit Bisa Ngilangi

Dr. Gymbro · · 4 min read
#supplements #pre workout #caffeine #arterial stiffness #cardiovascular health #beetroot #nitrate

Yen rutinitas pra‑latihanmu ngandelake sendok gedhé kafein, uji coba crossover anyar nunjukaké yèn arteri bisa dadi luwih kaku, sanajan tekanan darah tetep normal. Kajaba iku, studi iki uga nemokake yèn bubuk bit sing sugih nitrat, dipangan bebarengan karo kafein, bisa mulihaké perubahan arteri mau bali menyang tingkat plasebo.

Makalah iki diterbitaké ing Food & Function taun 2026 déning McLellan lan kanca‑kancane. Sanadyan ukurané cilik lan mung jangka pendek, panemune tetep dadi pandelengan menarik babagan cara loro suplemen paling populer kanggo kinerja silih interaksi ing sistem kardiovaskular.

Apa Sing Ditindakake Peneliti

Patang puluh loro wong enom sing sehat (17 priya, rata‑rata umur kira‑kira 24 taun) melu papat uji coba desain crossover acak, double‑blind, kontrol plasebo. Saben partisipan nyoba saben kondisi, dadi perbandingan luwih resik tinimbang studi sing misahake wong dadi grup.

Kondisi‑kondisi sing diuji:

  • PL: bubuk bit bebas nitrat (92 mg nitrat) tanpa kafein
  • CAF: bubuk bit bebas nitrat lan 6 mg/kg kafein
  • BR: bubuk bit sugih nitrat (400 mg nitrat) tanpa kafein
  • BR‑CAF: bubuk bit sugih nitrat lan 6 mg/kg kafein

Kanggo wong bobot 80 kg, 6 mg/kg padha karo watara 480 mg kafein – tingkat paling dhuwur sing asring diwènèhi produk pra‑latihan lan luwih dhuwur tinimbang siji cangkir kopi umumé. Peneliti ngukur tekanan darah brachial lan sentral lan indeks kekakuan arteri sadurunge lan 2,5 jam sawisé suplementasi. Fungsi endotel makrovaskular dipriksa mengko nganggo flow‑mediated dilation (FMD).

Asil Utama: Kafein Nambah Tandha Kekakuan

Kafein dewe nambah loro ukuran kekakuan arteri. Tekanan augmentasi munggah kira‑kira 3 mmHg, dibandhingaké 1 mmHg ing plasebo. Indeks augmentasi munggah kira‑kira 10 %, dene plasebo mung 4 % lan bubuk bit sugih nitrat dewe 1 %. Bédané signifikan sacara statistik (P antara 0,001 lan 0,007).

Tekanan lan indeks augmentasi nuduhaké pira gelombang tekanan refleks saka periferal nambah beban ing jantung. Arteri sing luwih kaku ngasilaké gelombang iki luwih cepet, nambah beban kerja jantung. Nilai sing luwih dhuwur umume dianggep ora becik kanggo kesehatan kardiovaskular.

Kejutan: Nitrat Mbatalaké Efek Kafein

Nalika bubuk bit 400 mg nitrat dipangan bareng kafein, kenaikan kasebut meh ilang. Tekanan augmentasi mung mundhak kira‑kira 1 mmHg lan indeks augmentasi mung 3 %, ora béda sacara signifikan karo plasebo utawa bit dewe (P = 0,505‑0,689).

Tes getih cocok karo ekspektasi jalur nitrat. Nitrit plasma luwih dhuwur ing loro kondisi bit sing sugih nitrat tinimbang plasebo utawa kafein dewe. Nitrit iku prekursor nitric oxide, sing mbantu pembuluh darah relaks. Nanging, tingkat siklik GMP ing plasma, molekul sinyal downstream, ora beda antarane kondisi, dadi mekanisme persisé durung jelas saka studi iki.

Apa Sing Ora Ganti

Penting ora nggedhekaké temuan iki. Sawetara perkara tetep statis:

  • Tekanan darah brachial ora owah sacara signifikan amarga kafein utawa bit.
  • Tekanan darah sentral uga tetep.
  • Flow‑mediated dilation, ukuran fungsi endotel makrovaskular, ora nuduhaké bedane.

Dadi judhul utama dudu yèn kafein nambah tekanan darah utawa ngrusak lapisan pembuluh. Efeké spesifik kanggo tandha gelombang refleksi sing nuduhaké kekakuan arteri. Iki sinyal sing alus, lan makna kanggo kesehatan jangka panjangé durung jelas saka siji dosis.

Takeaway Praktis

  • Dosis nitrat: Bubuk bit sing efektif nyedhiyakake 400 mg nitrat. Priksa label, amarga produk bit béda‑bèda lan akèh sing ora nyebutake kandhungan nitrat. Produk tanpa cathetan nitrat mung perkiraan.
  • Wektu panggunaan: Kafein lan nitrat dipangan bebarengan, lan pengukuran ditindakake 2,5 jam mengko. Iki kira‑kira pas karo jendela pra‑latihan, nanging studi ora nyoba wektu liya utawa latihan nyata.
  • Sapa sing perlu ngerti: Wong sing asring njupuk dosis kafein dhuwur sadurunge latihan, apamaneh sing nyampur macem‑macem produk stimulan, iku target utama. Wong sing mung ngombe siji cangkir kopi adoh banget saka dosis 6 mg/kg sing digunakake ing kéné.
  • Pendekatan wicaksana: Yen sampeyan wis nggunakake suplemen bit utawa nitrat kanggo ketahanan, nyawijikake karo kafein ora dadi risiko dhuwur adhedhasar data iki. Nanging, iki dudu alesan kanggo nambah dosis kafein.

Apa Sing Durung Diketahui

Watesan‑watesané gedhé:

  • Siji dosis, siji sesi. Ora ana bukti babagan panggunaan saben dina nganti minggu utawa taun.
  • Mung wong enom sing sehat. Wong tuwa, sing nduwèni hipertensi, utawa sing duwe penyakit vaskular bisa nanggapi béda.
  • Ora ana komponen latihan. Uji coba ngukur respon ing istirahat sawisé suplementasi, ora nalika utawa sawisé latihan.
  • Sampel cilik. Mung 24 partisipan, mayoritas priya, mbatesi generalisasi.
  • Mekanisme durung cetha. cGMP sing ora owah ninggalake pitakon carané nitrat ngasilaké efek.
  • Relevansi klinis. Apa kenaikan sementara indeks augmentasi duwé risiko nyata durung dibuktèkaké.

Kesimpulan

Uji coba crossover acak iki nuduhaké yèn dosis kafein pra‑latihan sing dhuwur bisa nambah tandha kekakuan arteri sakwisé, lan 400 mg nitrat saka bubuk bit bisa ngimbangi kenaikan iku. Tekanan darah lan fungsi endotel ora kena, mula ora ana sebab kanggo kuwatir. Iki temuan mekanistik awal sing nuduhaké cara berbasis panganan sing mungkin kanggo nyuda salah siji efek samping kardiovaskular saka panggunaan kafein sing gedhé. Nanging, uji coba sing luwih gedhé lan dawa ing populasi luwih manéka, bebarengan karo latihan, dibutuhaké sadurunge ngadopsi bit minangka "perisai" pelindung.

Original study

Read the original research on pubmed.ncbi.nlm.nih.gov →

This article summarizes published research for general information. It is not medical advice.

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Dr. Gymbro

Dr. Gymbro writes for Dr. Gymbro: science-backed fitness, nutrition & performance.

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